WHne the helium gas occupies 12.4 L at 23°C and 0.956 atm, then at 40°C and 0.956 atm the volume of the helium gas is 13.1 L.
How do you calculate the volume of helium gas ?We can use the combined gas law to solve this problem, which relates the pressure, volume, and temperature of a gas in a closed system. The well-known expression for the combined gas law is:
(P₁ x V₁) / T₁ = (P₂ x V₂) / T₂
We are given that P₁ = P₂ = 0.956 atm, V₁ = 12.4 L, T₁ = 23°C = 296 K, and T₂ = 40°C = 313 K. Putting these values into the gas formula, we obtain the following:
(0.956 atm x 12.4 L) / 296 K = (0.956 atm x V₂) / 313 K
Solving for V₂, we get:
V₂ = (0.956 atm x 12.4 L x 313 K) / (296 K x 0.956 atm) = 13.1 L
Therefore, the volume of the helium gas at 40°C and 0.956 atm is 13.1 L.
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the gain or loss of electrons from an atom results in the formation of a (an)
The formation of ions is an essential process in chemistry and is involved in many chemical reactions and compounds.
Atoms are composed of protons, neutrons, and electrons. The number of protons in an atom determines its atomic number and the element it represents. The electrons in an atom occupy different energy levels or shells, and these electrons participate in chemical reactions. The outermost shell of electrons, called the valence shell, is particularly important in chemical reactions because it determines the chemical properties of the atom.
When an atom gains or loses electrons, it becomes charged and is called an ion. The process of gaining or losing electrons is called ionization. When an atom loses one or more electrons, it becomes a positively charged ion called a cation. Cations have a smaller number of electrons than protons and have a net positive charge. For example, when the element sodium (Na) loses one electron, it becomes a sodium ion (Na+).
On the other hand, when an atom gains one or more electrons, it becomes a negatively charged ion called an anion. Anions have a larger number of electrons than protons and have a net negative charge. For example, when the element chlorine (Cl) gains one electron, it becomes a chloride ion (Cl-).
The formation of ions is a fundamental process in many chemical reactions. Ions can combine with each other to form ionic compounds, which are compounds composed of ions held together by electrostatic forces. For example, sodium ions (Na+) and chloride ions (Cl-) can combine to form sodium chloride (NaCl), which is common table salt.
Overall, the formation of ions is an essential process in chemistry and is involved in many chemical reactions and compounds.
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4. describe the relationship between the metal and water in terms of which is exothermic and which is endothermic.
Photoionization processes (e.g., N2 +hν → N2+ + e-) remove UV of <150 nm. Which photoreaction is the principal absorber of UV in the 150-200 nm range in the upper atmosphere?
a) N2 + hv ->2N
b) O2 + hv -> 2O
c) O3 + hv -> O2 + O
d) N2 + O2 + hv -> 2NO
e) NO + O2 + hv -> NO3
Ozone is the primary absorber of UV radiation in the 150-200 nm range in the upper atmosphere, and its depletion can have significant consequences for life on Earth.
UV radiation with wavelengths between 150-200 nm is highly energetic and can cause damage to living cells by breaking chemical bonds and damaging DNA. Therefore, it is important to prevent most of this radiation from reaching the Earth's surface where it can harm living organisms.
In the upper atmosphere, ozone (O3) plays a crucial role in absorbing this harmful UV radiation through the process of photodissociation. When a molecule of ozone absorbs a photon of UV radiation, it undergoes photodissociation or photolysis, which results in the dissociation of the ozone molecule into an oxygen molecule (O2) and an oxygen atom (O):
O3 + hv -> O2 + O
This process is highly efficient and can absorb more than 97% of the incoming UV radiation in the 150-200 nm range. The oxygen atoms produced in this process can then react with other oxygen molecules to form more ozone, thereby replenishing the ozone layer and continuing this protective cycle.
While other molecules such as nitrogen (N2) and oxygen (O2) can also absorb UV radiation in this range, they are much less efficient at doing so compared to ozone. Therefore, ozone is the primary absorber of UV radiation in the 150-200 nm range in the upper atmosphere, and its depletion can have significant consequences for life on Earth.
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what is the total number of joules of heat energy needed to raise the temperature of 10 grams of water from 20 c to 30 c
The total number of joules of heat energy needed to raise the temperature of 10 grams of water from 20°C to 30°C is 418.4 J. The specific heat capacity of water is 4.184 J/g·°C.
To find the total heat energy needed, we can use the formula:
Q = m·c·ΔT
where:
Q = heat energy (in Joules)
m = mass of the water (in grams)
c = specific heat capacity of water (4.184 J/g·°C)
ΔT = change in temperature (in °C)
Substituting the values given, we get:
Q = 10 g × 4.184 J/g·°C × (30°C - 20°C)
Q = 418.4 J
Therefore, the total number of joules of heat energy needed to raise the temperature of 10 grams of water from 20°C to 30°C is 418.4 J.
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an atomic anion with a charge of has the following electron configuration: 2s22p5what is the chemical symbol for the ion? how many electrons does the ion have?how many electrons are in the ion?
The chemical symbol for the ion with an atomic anion and a charge of -1, and electron configuration of 2s22p5 is Cl⁻. The Cl⁻ ion has 18 electrons.
This is because the electron configuration matches that of the element chlorine, which is found in group 7 of the periodic table. The Cl⁻ ion is formed when chlorine gains an extra electron to fill its valence shell and achieve a stable octet configuration.
The Cl⁻ ion has 18 electrons in total, as it has gained one extra electron compared to the neutral chlorine atom. The ion now has a full outer shell with 8 electrons, making it stable and less reactive than its neutral counterpart.
The Cl⁻ ion is commonly found in nature, particularly in the form of sodium chloride (NaCl) or table salt. The Cl⁻ ion is also used in various chemical processes, such as in the production of bleach and other disinfectants. Overall, the Cl⁻ ion plays an important role in many chemical reactions and is essential for maintaining the balance of charges in various compounds.
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at stp, what is the volume of 4.50 moles of nitrogen gas? at stp, what is the volume of 4.50 moles of nitrogen gas? 101 l 167 l 1230 l 60.7 l 3420 l
The volume of 4.50 moles of nitrogen gas at STP is approximately 101 L. So, the correct answer is 101 L.
At STP (standard temperature and pressure), the volume of one mole of any gas is 22.4 liters. Therefore, to find the volume of 4.50 moles of nitrogen gas at STP, we can simply multiply the number of moles by the molar volume:
At STP (Standard Temperature and Pressure), the volume of 4.50 moles of nitrogen gas (N2) can be calculated using the ideal gas law:
PV = nRT
Where P is the pressure (which is 1 atm at STP), V is the volume, n is the number of moles, R is the gas constant, and T is the temperature (which is 273.15 K at STP).
Rearranging this equation to solve for V, we get:
V = (nRT)/P
Substituting the values for n, R, P, and T, we get:
V = (4.50 mol x 0.08206 L atm K^-1 mol^-1 x 273.15 K)/1 atm
V = 101.3 L
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when a 2.5 liter vessel is filled with an unknown gas at stp, it weighs 2.75 g more than when it is evacuated. determine the molar mass of the unknown gas
The molar mass of the unknown gas is 27.0 g/mol.
According to the ideal gas law, PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature. At STP, the pressure is 1 atm, the volume is 2.5 L, and the temperature is 273.15 K.
To find the number of moles of gas present, we can rearrange the ideal gas law equation to solve for n:
n = PV/RT
Substituting the values at STP, we get:
n = (1 atm) x (2.5 L) / [(0.08206 L atm/mol K) x (273.15 K)]
n = 0.1018 moles
The difference in weight between the gas-filled vessel and the evacuated vessel is 2.75 g, which is the weight of 0.1018 moles of the unknown gas.
So the molar mass of the gas can be calculated as:
molar mass = mass / moles
molar mass = 2.75 g / 0.1018 mole
molar mass = 27.0 g/mol
Therefore, the molar mass of the unknown gas is 27.0 g/mol.
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The molar mass of the unknown gas is 27.0 g/mol.
According to the ideal gas law, PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the gas constant, and T is the temperature. At STP, the pressure is 1 atm, the volume is 2.5 L, and the temperature is 273.15 K.
To find the number of moles of gas present, we can rearrange the ideal gas law equation to solve for n:
n = PV/RT
Substituting the values at STP, we get:
n = (1 atm) x (2.5 L) / [(0.08206 L atm/mol K) x (273.15 K)]
n = 0.1018 moles
The difference in weight between the gas-filled vessel and the evacuated vessel is 2.75 g, which is the weight of 0.1018 moles of the unknown gas.
So the molar mass of the gas can be calculated as:
molar mass = mass / moles
molar mass = 2.75 g / 0.1018 mole
molar mass = 27.0 g/mol
Therefore, the molar mass of the unknown gas is 27.0 g/mol.
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Pi bonding occurs in each of the following species EXCEPT...
(A) CO2 (B) C2H4 (C) CN− (D) C6H6 (E) CH4
CH4 has only sigma bonds between the carbon and hydrogen atoms, and no pi bonds.
The answer is (E) CH4.
Pi bonding refers to the sharing of electrons between two atoms that occurs when two atomic orbitals with parallel electron spins overlap. Pi bonds are formed by the sideways overlap of two p orbitals.
In the given options, all except CH4 have pi bonds:
(A) CO2 has two pi bonds between the carbon atom and the oxygen atoms.
(B) C2H4 has a double bond between the two carbon atoms, which consists of one sigma bond and one pi bond.
(C) CN− has a triple bond between the carbon and nitrogen atoms, consisting of one sigma bond and two pi bonds.
(D) C6H6 has six pi bonds due to the delocalized pi electron system in the benzene ring.
In contrast, CH4 has only sigma bonds between the carbon and hydrogen atoms, and no pi bonds.
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A Carbon atom has a mass of 1.994 x10-23 g. If a sample of pure carbon has a mass of 42.552g, how many atoms would this contain? Show your work.
The sample of pure carbon would contain approximately 2.135 x 10²⁴ carbon atoms.
How many carbon atoms have masses that are equivalent to those in the periodic table?The majority of carbon atoms—98.93%—have masses of 12 atomic mass units. A mass of 13.00 atomic mass units is present in 1.07% of the carbon atoms. 14.) Identify one distinction between the nuclei of carbon-12 and carbon-13 atoms in terms of the subatomic particles that can be discovered there.
First, using the atomic mass of carbon, we must determine how many moles of carbon are present in the sample:
1 mole of carbon atoms = 12.01 g of carbon atoms (atomic mass of carbon)
42.552 g of carbon atoms / 12.01 g/mol = 3.545 moles of carbon atoms
Using Avogadro's number, we can then determine how many carbon atoms are present in the sample:
Number of carbon atoms = 3.545 moles of carbon atoms x 6.022 x 10²³ atoms/mole
Number of carbon atoms = 2.135 x 10²⁴ atoms
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which is a specific safety concern when handling the tlc developing solvent used in this experiment? keep cold, it is explosive at room temperature. keep away from open flames or hot surfaces. it forms hydrogen gas when combined with metals. do not mix with water.
A specific safety concern when handling the TLC developing solvent used in this experiment is to keep it away from open flames or hot surfaces. Option 2 is correct.
The TLC developing solvent used in this experiment is often a flammable organic solvent such as ethyl acetate or hexane. These solvents have a low flash point, which means they can ignite easily and burn rapidly if exposed to an ignition source such as an open flame or hot surface.
Therefore, it is important to keep the solvent away from open flames or hot surfaces to prevent fires and explosions. In addition, it is recommended to handle these solvents in a well-ventilated area to minimize the risk of inhalation or skin exposure. It is also important to avoid contact with reactive metals, as some solvents can react with metals to form hydrogen gas, which can be flammable or explosive.
Finally, these solvents should not be mixed with water, as they are immiscible and can form separate layers, which can cause splattering or other hazards. Hence Option 2 is correct.
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which of the following is a true statement regarding entropy? multiple choice question. the entropy of a substance is lowest in the solid phase and highest in the gas phase. the entropy of a system is the same regardless of whether it is in the solid or the gas phase. the entropy of a system is lowest in the gas phase and the highest in the solid phase. the entropy of a system is independent of its phase.
Answer:
Answer (Detailed Solution Below)
Explanation:
Option 3 : Substance in solid phase has the least entropy.
true or false a pure substance (such as h2o or iron) can only exist in three phases (solid, liquid, and gas)
A pure substance (such as H₂O or iron) can only exist in three phases (solid, liquid, and gas) - True.
A kind of matter with a predictable chemical composition and physical characteristics is referred to as a chemical substance. According to certain texts, a chemical compound cannot be physically divided into its component parts without rupturing chemical bonds. Chemical compounds, alloys, and simple substances (substances made up of a single chemical element) are all examples of chemical substances.
To distinguish them from mixes, chemical compounds are frequently referred to as 'pure'. Pure water is a popular illustration of a chemical substance; regardless of whether it is separated from a river or created in a lab, it has the same characteristics and hydrogen to oxygen ratio. Other chemicals that are frequently found in their purest forms are refined sugar (sucrose), gold, table salt (sodium chloride), and diamond (carbon). In reality, though, no material is completely pure, and chemical purity is determined by the chemical's intended application.
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if each orange sphere represents 0.010 mol of sulfate ion, how many moles of acid and of base reacted?
The number of moles of acid and base that react depends on the stoichiometry of the chemical reaction and the amounts of reactants used
Without additional information about the chemical reaction or system being referred to, we cannot determine the number of moles of acid and base that reacted.
If we assume that the orange spheres represent sulfate ions in a specific reaction, then we would need to know the stoichiometry of the reaction to determine the number of moles of acid and base that reacted.
For example, if the reaction involved sulfuric acid ([tex]H_2SO_4[/tex]) and sodium hydroxide (NaOH) and the orange spheres represent sulfate ions ([tex](SO_4)^{2-[/tex]), then the balanced chemical equation would be:
[tex]H_2SO_4 + 2NaOH - > Na_2SO_4 + 2H_2O[/tex]
In this case, we would need to know the amount of sodium hydroxide used to determine the number of moles of acid and base that reacted. If we know the number of orange spheres representing sulfate ions and the amount of sodium hydroxide used, we can determine the moles of acid and base that reacted.
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g consider a semiconductor with 10 13 donors/cm 3 which have a binding energy of 10 mev. (a) what is the concentration of extrinsic conduction electrons at 300 k? (b) assuming a gap energy of 1 ev (and m* ? m 0 ), what is the concentration of intrinsic conduction electrons? (c) which contribution is larger?
At 300 K, some of the donors will ionize, releasing electrons into the conduction band. The concentration of extrinsic conduction electrons can be calculated using the equation [tex]n = N_D * exp(-E_D/kT),[/tex] where n is the concentration of electrons, [tex]N_D[/tex] is the donor concentration, [tex]E_D[/tex] is the binding energy of the donors, k is Boltzmann's constant, and T is the temperature in Kelvin.
(b) At 300 K, some electrons will also be thermally excited into the conduction band, creating intrinsic conduction. The concentration of intrinsic conduction electrons can be calculated using the equation [tex]n_i = N_C * exp(-E_G/2kT)[/tex] , where [tex]n_i[/tex] is the concentration of electrons, [tex]N_C[/tex] is the effective density of states in the conduction band, and [tex]E_G[/tex] is the bandgap energy.
(c) The contribution of intrinsic conduction is generally smaller than that of extrinsic conduction, as the concentration of dopants is usually much higher than the intrinsic carrier concentration at room temperature.
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can you help me with this
The graph shows the changes in the phase of ice when it is heated. A graph is plotted with temperature in degree Celsius on the y axis and Time in minutes on the x axis. The temperature at time 0 minute is labeled A, the temperature at time 2 minutes is labeled B, the temperature at time 25 minutes is labeled C, the temperature at time 80 is labeled D. Graph consists of five parts consisting of straight lines. The first straight line joins points 0, A and 2, B. The second straight line is a horizontal line joining 2, B and 12, B. Third straight line joins 12, B and 25, C. Fourth straight line is a horizontal line which joins 25, C and 80, C. Fifth straight line joins 78, C and 80, D. Which of the following temperatures describes the value of A?
We can conclude that the value of A must be less than the value of B. Based on the graph, the value of B is around 0°C. So, we can estimate that the value of A is likely to be around -10°C to 0°C.
What is Temperature?
Temperature is a physical quantity that measures the degree of hotness or coldness of an object or substance. It is a measure of the average kinetic energy of the particles that make up a system.
In simpler terms, temperature is a measure of how fast the atoms and molecules in a substance are moving. When the particles are moving faster, the temperature is higher, and when they are moving slower, the temperature is lower.
Based on the given information, we know that at time 0 minutes, the temperature is labeled as A. Therefore, to find the temperature value of A, we need to look at the y-axis at time 0 minutes.
Since the temperature scale is not given, we cannot determine the numerical value of A directly. However, we can make some observations about the graph to infer the approximate value of A.
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if groundwater contaminant is not visible does that mean it is safe to drink? Explain
It depends on what you meant by saying not visible. Of it is not visible by using accurate measuring equipment then I think so, but if you mean that all transparent water is drinkable, then no. Think about this. When you put salt in water, you can't see it but it is still there: if you taste the water you can tell that there's salt in there. Let's say that instead of salt there are some bacteria, or some other type of salt which is not appropriate to drink at high levels, such as nitrates. I personally wouldn't recommend drinking from any type.of water unless you are not sure about its purity
it takes 500 j of work to compress quasi-statically 0.50 mol of an ideal gas to one-fifth its original volume. calculate the temperature of the gas, assuming it remains constant during the compression.
As the compression is carried out quasi-statically, the gas's temperature will not change during the process. The temperature of the gas is T= 60.65 K.
The temperature of the gas will remain constant during the compression process since it is being done quasi-statically.
This means that the temperature of the gas will remain constant throughout the compression process.
Since the amount of work (500 J) is given, the temperature of the gas can be determined using the equation U = (3/2)nRT, where U is the work, n is the number of moles, R is the ideal gas constant, and T is the temperature.
Solving for T, we find that the temperature of the gas is T = (2/3)(500 J)/(0.50 mol)(8.31 J/mol K) = 60.65 K.
Complete Question:
It takes 500 J of work to compress 0.50 mol of an ideal gas quasi-statically to one-fifth its original volume. What is the temperature of the gas, assuming it remains constant during the compression?
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Find the volume of a sample of wood that has a mass of 95. 1 g and a density of 0. 857 g/mL (How do you do this!)
The volume of the sample of wood is 110.9 mL.
Volume is the measure of the amount of space which is occupied by an object or the substance. It is usually expressed in units such as liters, milliliters, cubic meters, or cubic centimeters. The volume of a solid can be calculated by measuring its dimensions and using mathematical formulas, while the volume of a liquid can be measured directly using a graduated cylinder or a pipette.
To find the volume of the sample of wood, we can apply the following formula;
Density = Mass/Volume
Rearranging the formula, we get;
Volume = Mass/Density
Substituting the given values, we get:
Volume = 95.1 g / 0.857 g/mL
Volume = 110.9 mL
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2 NO(g)+Cl2(g)⇌2 NOCl(g) Kc=2000
A mixture of NO(g) and Cl
2
(g) is placed in a previously evacuated container and allowed to reach equilibrium according to the chemical equation shown above When the system reaches equilibrium, the reactants and products have the concentrations listed in the following table:
Species Concentration (M)
NO(g) 0.050
C12(g) 0.050
NOCl(g) 0.50
Which of the following is true if the volume of the container is decreased by one-half?
A. Q = 100, and the reaction will proceed toward reactants.
B. Q = 100, and the reaction will proceed toward products.
C. Q = 1000, and the reaction will proceed toward reactants.
D. Q = 1000, and the reaction will proceed toward products.
Neither A, B, C nor D. The equilibrium position will not be affected by the change in volume.
To determine how the equilibrium of the reaction 2 NO(g) + Cl₂(g) ⇌ 2 NOCl(g) will shift if the volume of the container is decreased by one-half, we first need to calculate the reaction quotient Q.
The balanced chemical equation for the reaction is:
2 NO(g) + Cl₂(g) ⇌ 2 NOCl(g)
At equilibrium, the concentrations of the species are:
[NO] = 0.050 M
[Cl2] = 0.050 M
[NOCl] = 0.50 M
Using these values, we can calculate the value of the reaction quotient Q:
Q [tex]= [NOCl]^2 / ([NO]^2[Cl2])[/tex]= [tex](0.50)^2 / ((0.050)^2 x 0.050)[/tex] = 1000
Now we compare the value of Q to the equilibrium constant Kc:
Kc =[tex][NOCl]^2 / ([NO]^2[Cl2])[/tex] = 2000
Since Q < Kc, we can conclude that the reaction has not yet reached equilibrium and that the forward reaction will proceed to reach equilibrium.
When the volume of the container is decreased by one-half, the concentration of all species will increase due to the decrease in volume. According to Le Chatelier's principle, the reaction will shift in the direction that reduces the total number of moles of gas.
In this case, the reaction produces two moles of gas on the left-hand side and two moles of gas on the right-hand side, so the total number of moles of gas does not change. Therefore, the volume change will not have an effect on the equilibrium position.
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The correct answer is: C. Q = 1000, and the reaction will proceed toward reactants.
How to determine the reactions at equilibrium?
To determine which statement is true if the volume of the container is decreased by one-half, we need to calculate the reaction quotient (Q) for the new conditions.
When the volume is decreased by half, the concentrations of all species will double:
NO(g): 0.050 * 2 = 0.100 M
Cl2(g): 0.050 * 2 = 0.100 M
NOCl(g): 0.50 * 2 = 1.00 M
Now, calculate Q using the new concentrations:
Q = [NOCl]^2 / ([NO]^2 * [Cl2])
Q = (1.00)^2 / ((0.100)^2 * (0.100))
Q = 1 / 0.001
Q = 1000
So, Q = 1000. Now, compare Q to Kc:
Q > Kc, meaning the reaction will proceed toward the reactants to reach equilibrium.
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Calculate the heat capacity, in joules per degree of 28.4 g of water. Specific heat of H2O() = 4.184 J/g.°C a) 28.4 J/°C b) 119 J/°C Oc) 6.8 J/°C d) 0.147J/°C
The heat capacity of 28.4 g of water is 118.8976 J/°C. The closest option to this answer is option b) 119 J/°C.
To calculate the heat capacity of 28.4 g of water, we need to use the formula:
Heat capacity = mass x specific heat
where mass is given as 28.4 g and specific heat of water is given as 4.184 J/g.°C.
So, substituting the values in the formula, we get:
Heat capacity = 28.4 g x 4.184 J/g.°C
Heat capacity = 118.8976 J/°C
To calculate the heat capacity of 28.4 g of water, you need to multiply the mass of water (m) by its specific heat (c). The formula for heat capacity (Q) is:
Q = m × c
Given:
m = 28.4 g
c = 4.184 J/g.°C
Substitute the values and perform the calculation:
Q = 28.4 g × 4.184 J/g.°C = 118.8 J/°C
The closest answer among the given options is:
b) 119 J/°C
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a random copolymer produced by polymerization of vinyl chloride and propylene has a number average molecular weight of 229,500 g/mol and a number degree of polymerization of 4,000. what is the average repeat unit molecular weight? select one: a. 62.5 g/mol b. 42.0 g/mol c. 57.4 g/mol d. 24.0 g/mol
The average repeat unit molecular weight for average molecular weight of 229,500 g/mol and a number degree of polymerization of 4,000 is equals to the 57.4 g/mol. So, option(c) is right one.
Polymers are large molecules made up of repeating structural units linked together. The degree of polymerization (DP) is the number of repeating units in the polymer molecule. The average molecular weight is the degree of polymerization (MP) multiplied by the molecular weight of the repeat unit (m) is written as [tex] \bar M_n = (DP)(m)[/tex]
We have a random copolymer produced by polymerization of vinyl chloride and propylene.
Average molecular weight= 229500 g/mol
Number degree of polymerization = 4000
Using the above formula, the average repeat unit molecular weight = 229500 g/mol/ 4000
= 57.37 ~ 57.4 g/mol
Hence, required value is 57.4 g/mol.
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phenacetin can be prepared from p-acetamidophenol, which has a molar mass of 151.16 g/mol, and bromoethane, which has a molar mass of 108.97 g/mol. the density of bromoethane is 1.47 g/ml. what is the yield in grams of phenacetin, which has a molar mass of 179.22 g/mol, possible when reacting 0.151 g of p-acetamidophenol with 0.12 ml of bromoethane?
The theoretical yield of phenacetin is 0.17922 g. However, the actual yield may be lower due to factors such as incomplete reaction, loss during purification, or experimental error.
To calculate the theoretical yield of phenacetin, we need to first determine the limiting reagent. The limiting reagent is the reactant that will be completely consumed in the reaction, thus limiting the amount of product that can be produced.
First, we need to convert the volume of bromoethane given in milliliters to grams, using its density:
0.12 ml x 1.47 g/ml = 0.1764 g bromoethane
Next, we can use the molar masses of p-acetamidophenol and bromoethane to determine the number of moles of each:
moles p-acetamidophenol = 0.151 g / 151.16 g/mol = 0.001 mol
moles bromoethane = 0.1764 g / 108.97 g/mol = 0.00162 mol
Since the reaction requires a 1:1 molar ratio of p-acetamidophenol to bromoethane, and the number of moles of p-acetamidophenol is smaller than the number of moles of bromoethane, p-acetamidophenol is the limiting reagent.
The theoretical yield of phenacetin can be calculated using the molar mass of phenacetin and the number of moles of p-acetamidophenol:
moles phenacetin = 0.001 mol p-acetamidophenol
mass phenacetin = 0.001 mol x 179.22 g/mol = 0.17922 g
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someone help please its a sience testtt
The equator of the sun rotates faster than the poles.
How does the rotation of the equator of the sun differ from the rotation of the poles of the sun?The equator of the sun rotates faster than its poles. This is known as differential rotation, and it is due to the fact that the sun is not a solid body, but is composed of gas and plasma. The equatorial regions of the sun rotate faster because they are farther from the center of the sun, where the gravitational pull is stronger, and thus experience less resistance to their motion.
The period of rotation of the equator of the sun is shorter than that of the poles. The equator rotates once every 25.4 days, while the poles rotate once every 36 days.
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. the two main sources for the increase of carbon dioxide in the atmosphere are . select one:
Answer:
combustion
respiration by humans
Explanation:
burning of wood leaves release carbon dioxide which is a green house gas and detrimental to the climate
25. j. chadwick discovered the neutron by bombarding with the popular projectile of the day, alpha particles. (a) if one of the reaction products was the then unknown neutron, what was the other product? (b) what is the q-value of this reaction?
(a) If one of the reaction products was the then unknown neutron, what was the other product is the C -12.
(b) The q-value of this reaction is the 5.9 × 10⁸ J.
The James Chadwick was discovered the neutron during the experiment involving the nuclear reaction in that the beryllium, bombarded with the alpha particles. The equation of the reaction is as :
⁴Be₉ + ²He₄ ----> ⁶C₁₂ + ⁰n₁
(a) If one of the reaction products was the then unknown neutron, what was the other product is the C -12.
(b) The q-value of this reaction is as :
q = mc²
Where,
The m is the mass
The c is the speed of the light.
m = 4.002603 + 2.014102
m = 1.988501
q = 1.988501 × 3 × 10⁸
q = 5.9 × 10⁸ J
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How many moles of h2 can be produced from x grams of mg in magnesium-aluminum alloy? the molar mass of mg is 24. 31 g/mol?
The number of moles of H₂ that can be produced from x grams of Mg is (x / 24.31)
The balanced chemical equation for the reaction between Mg and HCl is,
Mg + 2HCl → MgCl₂ + H₂
This equation shows that 1 mole of Mg reacts with 2 moles of HCl to produce 1 mole of H₂. Therefore, the number of moles of H₂ that can be produced from x grams of Mg can be calculated as follows:
Calculate the number of moles of Mg in x grams:
Number of moles of Mg = mass of Mg / molar mass of Mg
Number of moles of Mg = x / 24.31
Use the mole ratio between Mg and H₂ to calculate the number of moles of H₂ produced:
Number of moles of H₂ = Number of moles of Mg × (1 mole of H₂ / 1 mole of Mg)
Number of moles of H₂ = (x / 24.31) × (1/1)
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if something is oxidized, it is formally losing electrons. if something is oxidized, it is formally losing electrons. true false
The given statement, if something is oxidized, it is formally losing electrons. if something is oxidized, it is formally losing electrons is true.
When something is oxidized, it means that it is undergoing a chemical reaction where it loses electrons. This process can be represented using oxidation numbers, which are used to keep track of the transfer of electrons between atoms during a reaction. In general, oxidation is defined as the process by which an atom, ion or molecule loses one or more electrons. This leads to an increase in the oxidation state of the atom, ion or molecule.
There are various examples of oxidation reactions that occur in everyday life. For instance, when iron rusts, it is undergoing an oxidation reaction where it loses electrons to oxygen in the air. Similarly, when a potato is cut and exposed to air, it turns brown due to an oxidation reaction between the oxygen in the air and the enzymes in the potato. In both cases, the process of oxidation involves the loss of electrons from one substance to another.
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What is the most dangerous airborne particulates?
The most dangerous airborne particulates are known as PM2.5 (particulate matter 2.5 micrometers or smaller in diameter).
These fine particles can be inhaled deep into the lungs, potentially causing severe health problems, such as respiratory and cardiovascular issues. Due to their small size and ability to bypass our body's natural defenses, PM2.5 particulates pose a significant risk to human health.
The following are a few of the riskiest airborne particulates:
Fine particulate matter (PM2.5) is a term used to describe microscopic particles having a diameter of 2.5 micrometres or less that have the ability to enter the bloodstream and go deep into the lungs. Asthma, heart attacks, and lung cancer are just a few of the respiratory and cardiovascular issues that PM2.5 can bring on.
Paints, cleaning supplies, and building materials all include volatile organic compounds (VOCs), which are organic substances that can vaporise into the air at room temperature. VOCs can irritate the eyes, nose, and throat, induce headaches, and occasionally even lead to cancer.
The incomplete combustion of fossil fuels results in the deadly gas carbon monoxide (CO), which is present in gas heaters, stoves and vehicle exhaust. CO can lead to headaches, lightheadedness,
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The most dangerous airborne particulates are those that are small enough to reach the deepest parts of the lungs, such as the alveoli, where they can cause damage and inflammation. These particulates are referred to as fine particulate matter (PM2.5) and ultrafine particulate matter (PM0.1).
PM2.5 consists of particles with a diameter of 2.5 micrometers or less, while PM0.1 consists of particles with a diameter of 0.1 micrometers or less. These particulates can come from a variety of sources such as vehicle exhaust, industrial emissions, and wildfires.
Exposure to PM2.5 and PM0.1 has been linked to a range of health effects, including respiratory and cardiovascular disease, as well as premature death. These particulates can also carry toxic chemicals and heavy metals that can further increase their harmful effects on human health.
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which category of amino acid contains r groups that are hydrophobic? which category of amino acid contains r groups that are hydrophobic? polar acidic basic non-polar basic and acidic
The amino acid that contains the R groups that are hydrophobic are the non - polar.
The Amino acids are the building blocks of the molecules of the proteins. These contains the one hydrogen atom and the one amine group, the one carboxylic acid group and the one side chain that is the R group will be attached to the central carbon atom.
The side chains of the non polar amino acids includes the long carbon chains or the carbon rings, which makes them bulky. These are the hydrophobic, that means they repel the water. Therefore the non-polar amino acids are the hydrophobic.
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