Answer:
i hope this helps. sorry if it totally doesn't
A sample of an unknown gas weighs 0.419 grams and produced 5.00L of gas at 1.00atm (unknown gas only) and 298.15K, what is the molar mass (g/mole) of this unknown gas
Answer:
molar mass of unknown gas = 1.987 g/mol
Explanation:
First, the number of moles of the unknown gas is found
Using the ideal gas equation: PV = nRT
P = 1.00 atm, V = 5.00 L, T = 298.15 K, R = 0.082 L.atm.mol⁻¹K⁻¹
n = PV/RT
n = (1.00 atm * 5.00 L)/(298.15 K *0.082 L.atm.mol⁻¹K⁻¹)
n = 0.2109 moles
Molar mass = mass/ number of moles
molar mass = 0.419 g/ 0.2109 mols
molar mass of unknown gas = 1.987 g/mol
The molar mass of unknown gas by using ideal gas equation = 1.987 g/mol.
Ideal gas equationThis equation gives the relation between pressure, volume, temperature as given below:
[tex]PV = nRT[/tex]
P = 1.00 atm, V = 5.00 L, T = 298.15 K, R = 0.082 L.atm.mol⁻¹K⁻¹
Substitute the above values in the above equation as follows:
n = (1.00 atm * 5.00 L)/(298.15 K *0.082 L.atm.mol⁻¹K⁻¹)
n = 0.2109 moles
Formula for molar mass[tex]Molar mass = mass/ number of moles[/tex]
Calculate molar mass by using the above equation,
molar mass = 0.419 g/ 0.2109 moles
The molar mass of unknown gas = 1.987 g/mol
Find more information about ideal gas equation here,
brainly.com/question/4147359
Based on the visible cell structure, which of the following statements is true?
Answer:I think it would be the third one.
Explanation:
convert 575.1 mmHg to atm
Answer:
= .7567105263
Explanation:
1 atm = 760 mmHg
575.1 mmHg (1 atm/760mmHg) = .7567105263 atm
Question 11
4 pts
Using the formula 2H202 --> 2H2O + O2, if 7.30 moles of peroxide are
decomposed, how many moles of oxygen will be formed?
Answer:
3.65 mol O₂
Explanation:
Step 1: RxN
2H₂O₂ → 2H₂O + O₂
Step 2: Define
Given - 7.30 mol H₂O₂
Solve - x mol O₂
Step 3: Stoichiometry
[tex]7.30 \hspace{3} mol \hspace{3} H_2O_2(\frac{1 \hspace{3} mol \hspace{3} O_2}{2 \hspace{3} mol \hspace{3} H_2O_2} )[/tex] = 3.65 mol O₂
What is the approximate vapor pressure when the liquid water boils at about 50°C?
380 mmHg
760 mmHg
100 mmHg
5 mmHg
Answer:
380
Explanation:
What is the volume of a substance that has a mass of 59 g and a density of 1.98 g/mL?
(show all work)
Answer:
29.8
Explanation:
The formula for volume is mass/ density, so 59/1.98. 29.8 is the answer.
The energy associated with the motion and position of an object is called a.kinetic energy
b.potential energy
c.gravitational potential energy d.mechanical energy
Answer: The answer is D.
Explanation:
The form of energy associated with the motion, position, or shape of an object is called mechanical energy. An object's mechanical energy is a combination of its potential energy and its kinetic energy. The basketball has both potential energy and kinetic energy.
Hope this helps!
What do you need to measure the amount of energy in food
Answer:
u measure how much power it has
Explanation:
for example u can power a light bulb woth it if u can it was 100eg energy
True or False: Particles that are moving faster have a higher temperature
Answer:
true
Explanation:
I'm not sure why cause I dont know how to explain but it's TRUE
Answer:
True
Explanation:
The particles moving faster in a substance the hotter it gets.
1. Which statement describes a compound?
A. It contains a solute.
B. Its composition can vary.
C. Its combination of atoms never changes.
D. Its components keep separate properties.
2. Which item is NOT a type of matter?
A. force
B. mixture
C. element
D. compound
3. Which combination can be used to classify all the matter on Earth?
A. forces and energy
B. atoms and elements
C. solvents and solutes
D. substances and mixtures
what are the benefits of using supercritical fluids in EGS
Answer:
See detailed explanation.
Explanation:
Hello.
In this case, it is firstly necessary to cite that EGS accounts enhanced geothermal systems which are man-made reservoirs, placed where lots of hot rock is present but there is lack natural permeability, which requires a fluid to be injected into the subsurface to re-open it and therefore creating permeability.
Typically, water has been used for this purpose, but due to the current issue on saving water alternative methods such as supercritical fluids has been being implemented because they have better dynamic properties such as lower viscosities and therefore larger flow velocities, supercritical CO2 is easy and cheap to get as low temperatures are required to turn it in supercritical condition.
Best regards.!
What occurs after cytokinesis is completed at the end of meiosis I?
O Four haploid cells are formed.
O Two diploid cells are formed.
OTwo haploid cells are formed.
O Four diploid cells are formed.
Answer. After cytokinesis is completed at end of meiosis - I two haploid cells are formed.on:
Answer:
C. TWO HAPLOID CELLS ARE FORMED
Explanation:
I TOOK THE EDGUNITY TEST AND I GOT IT CORRECT
Determine the value of the equilibrium constant (report your answer to three significant figures) for the following reaction if an equilibrium mixture contains 0.010 mol of solid PbBr2, and is 0.0100 M in Pb2+ ions and 0.0250 M in Br1- ions. Use the notation 4.31e-5 to indicate a number such as 4.31 x 10-5.
Answer:
6.25e-6 is the value of the equilibrium constant
Explanation:
we have this equation
[tex]PbBr(s) ----- Pb^{2+}(aq) + 2Br(aq)[/tex]
When at a state of equilibrium,
we have the concentration of Pb^2+ to be 0.01
we have the concentration of Br^- to be 0.025
the equilibrium constant concentration of both pure solids and liquid s are said to be equal to 1
[PbBR2] = 1
such tht
Keq = [Pb^2+] x [Br-]^2
we already know the values of these from the above.
0.01x0.025^2
= 0.01 x 0.000625
= 0.00000625
= 6.25 x 10^-6
= 6.25e^-6
why are copper pipes used in place of old lead pipes for plumbing systems?
Calculate the pH of a solution containing a caffeine concentration of 455 mg/L . Express your answer to one decimal place.
Answer:
Explanation:
Caffeine is a weak base with pKb = 10.4
Kb = 10⁻¹⁰°⁴ = 3.98 x 10⁻¹¹
molecular weight of caffeine = 194.2
455 x 10⁻³ g / L = 455 x 10⁻³ / 194.2 moles / L
concentration of given solution a = 2.343 x 10⁻³ M
Let the caffeine be represented by B .
B + H₂O = BH + OH⁻
a - x x x
x² / ( a - x ) = Kb
x² / ( a - x ) = 3.98 x 10⁻¹¹
x is far less than a so a -x is almost equal to a
x² = 3.98 x 10⁻¹¹ x 2.343 x 10⁻³ = 9.32 x 10⁻¹⁴
x = 3.05 x 10⁻⁷
[ OH⁻ ] = 3.05 x 10⁻⁷
pOH = - log ( 3.05 x 10⁻⁷ )
= 7 - log 3.05
= 7 - 0.484 = 6.5
pH = 14 - 6.5 = 7.5
The pH of 455 mg/L of caffeine is 7.5
Using the formula;
Mass concentration = molar concentration × molar mass
Molar mass of caffeine = 194 g/mol
Mass concentration of caffeine = 455 mg/L
Molar concentration = Mass concentration/molar mass
Molar concentration = 455 × 10^-3g/L/194 g/mol
= 0.00235 M
Let Caffeine by depicted by the general formula BH
We can now set up the ICE table as follows;
:B + H2O ⇄ BH + OH^-
I 0.00235 0 0
C - x +x +x
E 0.00235 - x x x
Note that water is present in large excess
Again; pKb of caffeine =10.4
Kb = Antilog[-pKb]
Kb = Antilog [-10.4]
Kb = 3.98 × 10^-11
Kb = [BH] [OH^-]/[:B]
3.98 × 10^-11 = [x] [x]/[ 0.00235 - x ]
3.98 × 10^-11 [ 0.00235 - x ] = [x] [x]
9.4 × 10^-14 - 3.98 × 10^-11x = x^2
x^2 + 3.98 × 10^-11x - 9.4 × 10^-14 = 0
x = 3.1 × 10^-7 M
Recall [BH] = [OH^-] = 3.1 × 10^-7 M
Now;
pOH = - log [OH^-]
pOH = log [3.1 × 10^-7 M]
pOH = 6.5
But;
pH + pOH = 14
pH = 14 - pOH
pH = 14 - 6.5
pH = 7.5
The pH of 455 mg/L of caffeine is 7.5
Learn more: https://brainly.com/question/10038290
Missing parts
Caffeine (C8H10N4O2) is a weak base with a pKb of 10.4. Calculate the pH of a solution containing a caffeine concentration of 455 mg/L.
What happens when the elements in group 2 react with water?
Answer:
The Group 2 metals become more reactive towards the water as you go down the Group.
Explanation:
These all react with cold water with increasing vigour to give the metal hydroxide and hydrogen. ... You get less precipitate as you go down the Group because more of the hydroxide dissolves in the water. Summary of the trend in reactivity.
Please mark me brainliest! hope this helped!
God bless!
Answer each of the following questions with increases, decreases, or does not change.
a) If the intermolecular forces in a liquid increase, the normal boiling point of the liquid increases .
b) If the intermolecular forces in a liquid increase, the vapor pressure of the liquid does not change .
c) If the surface area of a liquid increases, the vapor pressure increases .
d) If the temperature of a liquid decreases, the equilibrium vapor pressure increases .
Drag and drop your selection from the following list to complete the answer:
does not change decreases increases
Answer:
1) Increases
2) decreases
3) increases
4) decreases
Explanation:
When the intermolecular forces in a liquid increases, the greater vapour pressure of the liquid decreases accordingly.
Since the vapour pressure is proportional to temperature, as temperature increases, the vapour pressure increases alongside.
As intermolecular forces increases, the boiling point increases accordingly since more energy is required to break intermolecular bonds.
Lastly, the greater the surface area, tell greater the vapour pressure since more liquid surface area is now available.
A teaspoon of salt, NaCl has a mass of about
5.0 g. How many formula units are in a
teaspoon of salt?
Answer: The answer is 5.15x10^22
Explanation:
The formula unit present in a teaspoon of salt [tex]NaCl[/tex] having a mass of about 5.0 g is [tex]5.15 \times10^{22}[/tex] formula units.
Molar mass, also known as molecular weight, is the mass of one mole of a substance. It is calculated by summing up the atomic masses of all the atoms in a molecule. The unit of molar mass is grams per mole (g/mol).
Now, to determine the number of formula units in a teaspoon of salt (NaCl), we need to use Avogadro's number and the molar mass of NaCl.
Avogadro's number [tex](N_a)[/tex] is approximately. [tex]6.022 \times10^{23}[/tex] formula units per mole.
The molar mass of [tex]NaCl[/tex] is the sum of the atomic masses of sodium (Na) and chlorine ([tex]Cl[/tex]), which are approximately 22.99 g/mol and 35.45 g/mol, respectively.
To calculate the number of formula units in 5.0 g of [tex]NaCl[/tex], we can follow these steps:
Now, calculate the number of moles of [tex]NaCl[/tex] using its molar mass:
Moles = Mass / Molar mass
Moles = [tex]5.0 g[/tex] / [tex](22.99 g/mol + 35.45 g/mol)[/tex]
Calculate the number of formula units using Avogadro's number:
Formula units = [tex]Moles \times Avogadro's number[/tex]
Let's perform the calculation:
Molar mass of [tex]NaCl[/tex]= [tex]22.99 g/mol + 35.45 g/mol = 58.44 g/mol[/tex]
Moles of [tex]NaCl[/tex] = [tex]5.0 g[/tex] / [tex]58.44 g/mol[/tex] ≈ [tex]0.0856 mol[/tex]
Formula units = [tex]0.0856 mol \times (6.022 \times 10^{23})[/tex] formula units/mol ≈ [tex]5.15 \times10^{22}[/tex]formula units.
Therefore, there are approximately [tex]5.15 \times10^{22}[/tex] formula units in a teaspoon of salt ([tex]NaCl[/tex]) having mass [tex]5.0 g[/tex].
Learn more molar mass about here:
https://brainly.com/question/31545539
#SPJ2
An ideal gaseous reaction (which is a hypothetical gaseous reaction that conforms to the laws governing gas behavior) occurs at a constant pressure of 35.0 atm and releases 74.6 kJ of heat. Before the reaction, the volume of the system was 8.20 L . After the reaction, the volume of the system was 2.80 L . Calculate the total internal energy change, ΔE, in kilojoules.
Answer:
ΔU = −55.45 kJ
Explanation:
From first law of thermodynamics in chemistry, we have;
ΔU = Q + W
where;
ΔU is change in internal energy
Q is the net heat transfer
W is the net work done
We are given;
Q = 74.6 kJ
But Q will be negative since heat is released
Thus;
ΔU = -74.6 kJ + W
We are given;
Constant pressure; P = 35 atm = 35 × 101325 = 3546375 N/m²
Volume before reaction; Vi = 8.2 L = 0.0082 m³
Volume after reaction; V_f = 2.8 L = 0.0028 m³
Now,
W = -P(V_f - V_i)
W = - 3546375(0.0028 - 0.0082)
W = 19.15 KJ
Thus;
ΔU = Q + W
ΔU = -74.6 kJ + 19.15 KJ =
ΔU = −55.45 kJ
help me please loves
Answer:
K and ba
Explanation:
Answer: K and Ba
Explanation:
The lewis dot notation for two atoms is shown. What is represented by this notation? K loses one portion to CI, K gains one portion from CI, K loses one electron to CI, K gains one electron from CI
Answer:
K loses one electron to CI
Explanation:
The lewis electron dot notation shows only the chemical symbol of the element surrounded by dots to represent the valence electrons.
We have atom of K with one valence electrons
Cl with 7 valence electrons
For an electrostatic attraction to occur, both particles must be charged. To do this, one of the species must lose an electron, and the other gains it.
This will make both species attain a stable octet;
Hence, K will lose 1 electron and Cl will gain the electrons.
Answer:
C: K loses one electron to CI
Explanation:
I took the test and got it correct!!
Calcium reacts with sulfur forming calcium sulfide. What is the theoretical yield (g) of CaS(s) that could be prepared from 7.19 g of Ca(s) and 2.67 g of sulfur(s)? Enter your answer with two decimal places. Do not type units with your answer.
Answer:
The theoretical yield of CaS is 6.01 g.
Explanation:
The balanced reaction is given as:
[tex]Ca+S\rightarrow CaS[/tex]
The molar mass of Ca and S is 40.08 and 32.065 g/mol respectively.
Number of moles = [tex]\frac{Mass}{Molar Mass}[/tex]
So, 7.19 g of Ca contains [tex](\frac{7.19}{40.08})[/tex] mol of Ca or 0.179 mol of Ca
Also, 2.67 g of S contains [tex](\frac{2.67}{32.065})[/tex] mol of S or 0.0833 mol of S
According to the balanced equation:
1 mol of Ca produces 1 mol of CaS
So, 0.179 mol of Ca produces 0.179 mol of CaS
According to the balanced equation:
1 mol of S produces 1 mol of CaS
So, 0.0833 mol of S produces 0.0833 mol of CaS
As the least number of mol of CaS (product) is produced from S , therefore, S is the limiting reactant.
So, thoretically, 0.0833 mol of CaS is produced.
The molar mass of CaS is 72.143 g/mol.
So, the mass of 0.0833 mol of CaS is [tex](0.0833\times 72.143)[/tex] g or 6.01 g
Hence, the theoretical yield of CaS is 6.01 g.
What is the pressure if the height of a column of mercury is 0.20 m and the density of mercury is 13,600 kg/m3? (remember, gravity is 9.81 m/s2)
Answer:
[tex]p=26683.2Pa[/tex]
Explanation:
Hello,
In this case, since the pressure is computed via:
[tex]p=h*\rho*g[/tex]
Whereas h is the 0.520-m height, [tex]\rho[/tex] is the 13600-kg/m³ density and the g the 9.81-m/s² gravity. Thus, the pressure in Pa is:
[tex]p=0.20m*13,600 \frac{kg}{m^3} *9.81\frac{m}{s^2} \\\\p=26683.2\frac{kg*\frac{m}{s^2} }{m^2} =26683.2\frac{N}{m^2}\\ \\p=26683.2Pa[/tex]
Best regards.
Calculate the density of the aluminum cylinder with a diameter 0f 1.3 cm weighing 18 grams. Height of the cylinder is 5.2 Cm. Find percent error (Actual density of Aluminum is 2.7 g/cm3). (Formula for volume of cylinder is πr2h)
Answer:
Percent error = 3.7%
Explanation:
Given data:
Density of Al cylinder = ?
Weight of cylinder = 18 g
Diameter = 1.3 cm
Height = 5.2 cm
Actual density of Al = 2.7 g/cm³
Percent error = ?
Solution:
First of all we will calculate the volume of cylinder through given formula.
V = πr²h
r = diameter /2
V = 22/7 × (0.65 cm)²× 5.2 cm
V = 22/7 × 0.4225cm²× 5.2 cm
V = 6.89 cm³
Now we will calculate the density.
d = m/v
d = 18 g/ 6.89 cm³
d = 2.6 g/cm³
Percent error:
Percent error = measured value - actual value /actual value × 100
Percent error = 2.6g/cm³ - 2.7g/cm³ /2.7g/cm³ × 100
Percent error = 3.7%
Negative sign shows that measured or experimental value is less than actual value.
Label the parts of the electric circuit that best correspond to the heart, arteries, veins, and cells.
Answer:
1 ➡️ Cells
2 ➡️ Arteries
3 ➡️ Veins
4 ➡️ Heart
Explanation:
The parts of the electric circuit that best correspond to the heart, arteries, veins, and cells have been properly labeled.
The circulatory system involves the transportation of nutrients, oxygen and water by blood to other the parts of the body.
From the electric circuit, we see that arteries transport blood away from the heart to the other cells in the body. The veins actually return the blood back to the heart from the cells. The heart pumps the blood
The electric circuity diagram has the label 1 bulb analogous to cell, label 2 analogous to arteries, label 3 analogous to veins, and label 4 cell analogous to heart.
What is an electric circuit?The electric circuit has been given as the power source and the conducting wires that allows the flow of the current in the circuit.
In the human body, the heart has been transported the oxygenated blood through the arteries to the cell and carried the deoxygenated blood from the cells back to the heart via veins.
In the circuit, the battery has been the source of the power/blood. The current has been carried from the heart to the cell/bulb through the arteries labeled, 2, and transported back to the battery via veins labeled 3.
Learn more about the electric circuits, here:
https://brainly.com/question/21075693
Which of the following is a good definition of matter?
O A. Anything that is made up of light and gravity
O B. Anything that has mass and takes up space
O C. Anything that produces heat and mass
O D. Anything that has energy and creates heat
Answer:
B
Explanation:
I did the question before and got it right.
The normal boiling point of benzene is 80.1°C. What is its enthalpy of vaporization if the vapor pressure at 26.1°C is 100 torr?
The heat of vaporization of benzene is required.
The heat of vaporization of benzene is 33009 J/kg.
[tex]T_0[/tex] = Normal boiling point = 80.1+273.15 K
[tex]T_B[/tex] = Boiling point at given pressure = 26.1+273.15 K
[tex]R[/tex] = Gas constant = 8.314 J/mol K
[tex]P[/tex] = Pressure at given [tex]T_B[/tex] = 100 torr
[tex]\Delta H[/tex] = Heat of vaporization
From the Clausius–Clapeyron equation
[tex]\dfrac{1}{T_B}=\dfrac{1}{T_0}-\dfrac{R\ln(\dfrac{P}{P_0})}{\Delta H}\\\Rightarrow \Delta H=\dfrac{R\ln\dfrac{P}{P_0}}{\dfrac{1}{T_0}-\dfrac{1}{T_B}}\\\Rightarrow \Delta H=\dfrac{8.314\times \ln\left(\frac{100}{760}\right)}{\frac{1}{80.1+273.15}-\frac{1}{26.1+273.15}}\\\Rightarrow \Delta H=33008.99\ \text{J/kg}[/tex]
The heat of vaporization of benzene is 33009 J/kg.
Learn more:
https://brainly.com/question/13878485
https://brainly.com/question/1077674
What can the chemical formula tell us about a compound?
Answer:
A chemical formula tells us the number of atoms of each element that is in a compound. It contains the symbols of the atoms for the elements present in the compound as well as how many there are for each element in the form of subscripts.
Hope this helps! please mark me brainliest!
God bless :)
Which of the following is an Elementary compound?
A. CO2
B. N2
C. SO2
D. H2S
heeeeeeeeeelp please please please
Answer:
Explanation:
In my opinion the answer should be SO2
Answer:
a should be answer i think.
Scientists are experimenting with pure samples of isotope X which is radioactive. The sample has a mass of 20. Grams. The half-life was measured to be 232 seconds. There is a second sample that weighs 80 grams. What is the half-life of the second sample
Answer:
Explanation:
Half life of radioactive materials do not depend upon the mass of the material . It only depends upon the nature of radioactive materials . The half life of 20 g is 232 seconds . That means 20 gram will be reduced to 10 gram in 232 seconds .
Half life of 80 gram is also 232 seconds . So , 80 gram will be reduced to 40 gram in 232 second .