Answer:
D
Explanation:
Universe consits of galaxies, galaxies consit of solar systems, and solar systems consist of planets
is 3NaOH + H3PO4--->Na3PO4 + 3H2O balanced?
Answer:
Yes
Explanation:
3NaOH + H3PO4
3Na + 3O + 3H + 3H + P + 4O
3Na + 7O + 6H + P
Na3PO4 + 3H2O
3Na + P + 4O + 6H + 3O
3Na + 7O + 6H + P
Given that the enthalpy of vaporization for water is:
H2O(1) ►H2O(g)
Hvap = + 44.0 kJ/mole
Calculate H for each of the following processes:
a. Evaporating 3.00 moles of water
b. Evaporating 3.00 grams of water
c. Condensing 20.0 grams of water
Answer:h
Explanation:
From the table of data, substance C will have the least of the original amount remaining after 30 days even though it started with the most.
which is the best explanation for this answer?
A)Substances A and B are not as radioactive since they have longer half-lives.
B)The states of matter for substances A & B are more volatile than substance C.
C)Substances that start with large amounts will always decay at faster rates.
D)Substance C goes through a significantly larger amount of half-lives compared to the other substances.
Answer:
D)Substance C goes through a significantly larger amount of half-lives compared to the other substances.
Explanation:
Half life refers to the time taken for a radioactive isotope to decay to half of the original amount of radioactive substance present initially.
The shorter the half life of a radioactive substance, the more the amount of half-lives the substance undergoes within the given time period. Substance A will undergo five half lives within 30 days. Substance B will undergo six half lives within 30 days while substance C will undergo ten half lives within 30 days.
Since Substance C undergoes the highest amount of half lives within 30 days, substance C will have the least of the original amount remaining after 30 days even though it started with the most.
An isotope contains 56 protons, 54 electrons, and 74 neutrons. What is the identity of the isotope? Choose 1 answer:
Answer:
Barium.
Explanation:
Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number Z. But in the nucleus of each element it is also possible to find neutrons, whose number can vary. The atomic mass (A) is obtained by adding the number of protons and neutrons in a given nucleus.
The same chemical element can be made up of different atoms, that is, their atomic numbers are the same, but the number of neutrons is different. These atoms are called isotopes of the element. Isotopes means "same place", that is, since all the isotopes of an element have the same atomic number, they occupy the same place in the Periodic Table. So if a neutron is added to an atom, it becomes an isotope of that chemical element.
The isotopes of an element have the same chemical properties, but differ somewhat in their physical properties.
Barium has an atomic number of 56 (number of protons). Also, the mass number of this barium isotope is 130 (56 protons + 76 neutrons). Finally, since it has 54 electrons, two negatively charged electrons less than the number of positively charged protons, this isotope is a cation with oxidation number +2.
Is the formation of CO2(g) from its elements endothermic or exothermic?
Exothermic because the ΔH is negative.
Endothermic because the ΔH is negative.
Endothermic because the ΔH is positive.
Exothermic because the ΔH is positive.
Answer: Exothermic because the ΔH is negative.
Explanation:
The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states.
[tex]C(s)+O_2(g)\rightarrow CO_2(g)[/tex]
Exothermic reactions are those reactions in which heat is released and [tex]\Delta H[/tex] is negative.Endothermic reactions are those reactions in which heat is absorbed and [tex]\Delta H[/tex] is positive.
The reaction is exothermic as the heat is released during the formation of [tex]CO_2[/tex] as heat of formation of [tex]CO_2[/tex] is negative.
The process of energy being captured
by plants from the sun and then
transferred from one organism to the
next in the food chain is called
A food flow
B energy flow
C nutrient flow
D water flow
Answer:
B
Explanation:
I am not sure but I think it is B. Out of all the answers that one makes sense.
What causes the ocean tides to change from high tide to low tide?
How many grams of NaCl are in 3.5 mol of NaCl? Also, how many moles of NaCl are in 150 g of NaCl?
Answer:
204.5505 grams
2.5666 moles
Explanation:
For the first question, multiply 3.5 (# of moles) by 58.443 (g/mol for NaCl).
58.443 * 3.5
I'll distribute 3.5 into 58.443.
(3.5 * 50) + (3.5 * 8) + (3.5 * 0.4) + (3.5 * 0.04) + (3.5 * 0.003)
175 + 28 + 1.4 + 0.14 + 0.0105
203 + 1.4 + 0.14 + 0.0105
204.4 + 0.14 + 0.0105
204.54 + 0.0105
204.5505 grams
There are 204.5505 grams in 3.5 moles of NaCl.
For the second question, divide 150 (# of grams) by 58.443 (g/mol for NaCl). I'll convert both into fractions.
150/1 * 1000/58443
150000/58443
2.56660336 moles
2.5666 moles (rounded to 4 places to keep consistency with the first answer) are in 150 grams of NaCl.
11) How many grams are in 2.3 moles of magnesium chloride, MgCl,?
Answer:
218.98 grams
Explanation:
Given that,
No. of moles, n = 2.3
The molar mass of magnesium chloride is 95.211 g/mol.
We need to find the mass of 2.3 moles of magnesium chloride.
We know that,
No. of moles = given mass/molar mass
Let m be the given mass. So,
[tex]m=n\times M\\\\=2.3\times 95.211 \\\\=218.98\ g[/tex]
So, the required mass is equal to 218.98 grams.
what are two products that contain ammonia?
what is the nature of salt which is formed by the combination of weak acid and strong base And have a great day ❤️
One use of CaCl2 is for salting roads in the winter. How much would the freezing point of water decrease if a 3.23 molal (m) solution of CaCl2 were applied? (Kf = 1.86°C/(mol/kg) for water and i = 3 for CaCl2.)
Answer:
Freezing point of water will decrease to -18.02°C
Explanation:
We start from the formula for freezing point depression, one of the colligative properties.
ΔT = Kf . m . i
ΔT = Freezing T° of pure solvent - Freezing T° of solution
m = molality
Kf = Cyoscopic constant (specific for each solvent)
i = numbers of ions dissolved (Van't Hoff factor)
CaCl₂ → Ca²⁺ + 2Cl⁻ i = 3
We replace each data:
0°C - T° F) = 1.86°C/m . 3.23 m . 3
T°F = - 18.02°C
Nevada's annual precipitation averages between 21 and 24 cm. In comparison,Washington state averages between 96 and 97 cm of precipitation per year. Which of these factors has the greatest impact on the difference in precipitation between these two states?
Answer:
Mountain ranges and prevailing winds.
Explanation:
Mountain ranges and prevailing winds are the factors that is responsible for the difference in the precipitation between Nevada and Washington states. The Washington state is located along the coastal region of pacific ocean and having more mountain ranges which causes more rainfall in that region while on the other hand, Nevada state comprise of plateau, basins and far away from the ocean which is the main cause of lower rainfall as compared to Washington state.
A solution with a pOH level of 9.2 would be considered as a basic, acidic, or neutral.
Answer:
It would be Basic.
Explanation:
The higher the number, the more basic it is.
Answer:
its basic solution
Explanation:
b/c the pH value greater than7 base
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what happens to halogens on going top to bottom in their group
they remain as they are and don't change their type
Guys what is this plz
Answer:
nunya
Explanation:
business
A scientist is investigating which type of medicine would dissolve faster, a solid pill or a scoop of powder. Which hypothesis
should the scientist develop given prior knowledge about surface area?
A. Solid pills have more surface area and will take longer to dissolve.
B. Powders have less surface area and will dissolve faster.
C. Solid pills have less surface area and will not dissolve.
D. Powders have more surface area and will dissolve faster.
B.
because a solute with a smaller surface area will dissolve faster
Which of the following statements correctly describes the relationship between volume and temperature( moles and pressure of gas are constant)
Answer:
pressure of gas are constant describe the relationship between moles and temprature
The statements correctly describes the relationship between volume and temperature is pressure of gas are constant.
What is pressure ?The force delivered perpendicularly to an object's surface per unit area across which that force is dispersed is known as pressure. In comparison to the surrounding pressure, gauge pressure is the pressure. Pressure is expressed using a variety of units.
The volume of a gas is directly proportional to the number of moles of gas when both temperature and pressure are constant. The pressure of a gas is directly proportional to the number of moles of gas when both temperature and volume are constant.
In layman's words, the volume of a fixed mass of gas is exactly proportional to temperature at constant pressure.
Thus, If the pressure and temperature remain constant, the volume of a gas is directly proportional to the number of moles in the gas.
To learn more about the pressure, follow the link;
https://brainly.com/question/28169433
#SPJ12
what are the three major types of water pollutants? Name and describe a few examples for each one.
Answer:
b
Explanation:
Identify three sources of point-source pollution.
what do opposite electric forces do
Answer:
Charges that are opposite each other, such as positive and negative charges, draw each other. Like charges repel each other, such as two negative charges or two positive charges.
Explanation:
Answer:
Opposite electric forces attract each other.
Like if it's positive and negative they will come together.
If they are the same(positive and positive or negative and negative) they will repel each other.
Explanation:
How many moles of methane gas are required when there are 7.55 grams of oxygen gas available? Please someone explain how to solve this problem, I would really appreciate it.
Answer:
0.236 moles of methane gas are required when there are 7.55 grams of oxygen gas available.
Explanation:
The balanced reaction is
CH₄ + 2 O₂ → CO₂ + 2 H₂O
By reaction stoichiometry (that is, the ratio of reactants and products in the reaction), the following amounts of moles of each compound participate in the reaction:
CH₄: 1 mole O₂: 2 moles CO₂: 1 mole H₂O: 2 molesBeing the molar mass of each compound:
CH₄: 16 g/mole O₂: 32 g/moleCO₂: 44 g/mole H₂O: 18 g/moleThen, by reaction stoichiometry, the following mass amounts of each compound participate in the reaction:
CH₄: 1 moles* 16 g/mole= 16 gramsO₂: 2 moles* 32 g/mole= 64 gramsCO₂: 1 mole* 44 g/mole= 44 grams H₂O: 2 moles* 18 g/mole= 36 gramsSo, you can apply the following rule of three: if by reaction stoichiometry 64 grams of oxygen react with 2 moles of methane, 7.55 grams of oxygen react with how many moles of methane?
[tex]moles of methane=\frac{7.55 grams of oxygen*2 moles of methane}{64 grams of oxygen}[/tex]
moles of methane= 0.236
0.236 moles of methane gas are required when there are 7.55 grams of oxygen gas available.
A given sample of gas has a volume of 5.20 L at 60.°C and 1.00 atm pressure. Calculate its pressure if the volume is changed to 6.00 L and the temperature to 27°C (assume the amount of gas does not change)
Answer:
0.78 atm
Explanation:
Applying general gas equation
PV/T= P'V'/T'................ Equation 1
Where P = initial pressure, T = Initial temperature, V = Initial Volume, P' = Final pressure, V' = Final Volume, T' = Final Temperature.
make P' the subject of the equation
P' = PVT'/TV'.............. Equation 2
From the question,
Given: P = 1.00 atm, V = 5.20 L, T = 60°C = (273+60) = 333K, V' = 6.00 L, T' = 27°C = (27+273)K = 300 K
Substitute these values into equation 2
P' = (1×5.2×300)/(333×6)
P' = 1560/1998
P' = 0.78 atm.
H2CO3 -> H2O + CO2 What type of chemical reaction is taking place in this
chemical equation? *
O Synthesis
Decomposition
Single Replacement
Double Replacement
Combustion
Answer: decomposition
Explanation: one molecule forms tro molecules
How many moles of H2O are in 359 grams of H2O
Answer:
359
i think
Explanation:
A squirrel ran 20 meters along the fence at a constant speed for 10
seconds. It stopped for 15 seconds and then quickly ran another 30 meters
at a constant speed for 15 seconds.*
A
B
Answer:
It's D
Explanation:
Sorry for the late answer. Since the squirrel ran constant speed for 10 seconds and it ran 20 meters the first point would be at (10,20) then since it stopped to rest for 15 seconds the next point would be (25,20) finally since it ran another 30 meters for 15 more seconds the next point would be at (40,50). Sorry if the answer isn't the best, i'm bad at explaining ;w;
Multiple Choice. For each statement, circle the correct answer.
9. Most of the energy that drives the water cycle comes from
a. The Sun
b. Earth's cores
c. Earth's oceans d. the equator
10.
is the driving force behind excess runoff after a big precipitation event.
a. precipitation b. steepness of a hill c. gravity
d. solar radiation
Draw the product you expect from the reaction of (R)-2-bromooctane with -CN. Use the wedge/hash bond tools to indicate stereochemistry where it exists. Include H atoms at chiral centers only. If a group is achiral, do not use wedged or hashed bonds on it.
Answer:
See explanation and image attached
Explanation:
The reaction between (R)-2-bromooctane and -CN^- is an SN2 reaction. An SN2 reaction involves a synchronous attack of the nucleophile as the leaving group is departing.
This leads to a five member transition state in which a bond is being broken and another is being made. Since the nucleophile attacks from the backside, SN2 mechanism leads to inversion of configuration as shown in the image attached.
How many grams are in 1,000 Lutheran of C2H4
Answer:
28.05316 grams
Explanation:
Which has the most gravitational potential energy- a 10 kg ball that is 2 meters high or a 10 kg ball that is 4 meters high?
Answer:
The 10 kg ball that is 4 meters high is greater than a 10 kg ball that is 2 meters high
Explanation:
From the question,
Gravitational Potential Energy of the first ball
P.E1 = mgh.................... Equation 1
Where P.E1 = Gravitational Potential Energy of the first ball, m = mass of the first ball, h = height of the first ball, g = acceleration due to gravity.
Given: m = 10 kg, h = 2 m
Constant: g = 9.8 m/s²
Substitute these values into equation 1
P.E1 = 10×2×9.8
P.E1 = 196 J.
Similarly,
Gravitational potential energy of the second ball is
P.E2 = m'gh'................... Equation 2
Where P.E2 = Gravitational potential Energy of the second ball, m' = mass of the second ball, h' = height of the second ball.
Given; m' = 10 kg, h' = 4 m
Substitute these values into equation 2
P.E2 = 10×4×9.8
P.E2 = 392 J
From the above calculation,
P.E2 is greater than P.E1.
Hence, the 10 kg ball that is 4 meters high is greater than a 10 kg ball that is 2 meters high