Can somebody please help me!!

A 0.529-g sample of gas occupies 125 ml at 60. cm of hg and 25°c. what is the molar mass of the gas?

Llana [10]

Let's assume that the gas has ideal gas behavior. 
Then we can use ideal gas formula,
PV = nRT

Where, P is the pressure of the gas (Pa), V is the volume of the gas (m³), n is the number of moles of gas (mol), R is the universal gas constant ( 8.314 J mol⁻¹ K⁻¹) and T is temperature in Kelvin.

P = 60 cm Hg = 79993.4 Pa
V = 125 mL = 125 x 10⁻⁶ m³

n = ?

R = 8.314 J mol⁻¹ K⁻¹
T = 25 °C = 298 K

By substitution,
79993.4 Pa x 125 x 10⁻⁶ m³ = n x 8.314 J mol⁻¹ K⁻¹ x 298 K
n = 4.0359 x 10⁻³ mol

Hence, moles of the gas = 4.0359 x 10⁻³ mol

Moles = mass / molar mass

Mass of the gas = 0.529 g

Molar mass of the gas = mass / number of moles
= 0.529 g / 4.0359 x 10⁻³ mol
 = 131.07 g mol⁻¹

Hence, the molar mass of the given gas is 131.07 g mol⁻¹

4 0

2 years ago

Which of the following gives the molarity of a 17.0% by mass solution of sodium acetate, CH 3COONa (molar mass = 82.0 g/mol) in

weeeeeb [17]

Answer:

The molarity of this solution is 2.26 M (option D)

Explanation:

Step 1: Data given

Mass % = 17%

Molar mass of CH3COONa = 82.0 g/mol

Density of the solution = 1.09 g/mL

Step 2:

Assume the mass of the solution is 1.00 gram

⇒ 17.0 % CH3COONa = 0.17 grams

⇒ 83.0 % H2O = 0.83 grams

Step 3:

Density = 1.09 g/mL

Volume of the solution = total mass / density of solution

Volume of solution : 1.00 grams / 1.09 g/mL

Volume of the solution = 0.917 mL = 0.000917 L

Step 4: Calculate number of moles of CH3COONa

Number of moles = Mass / molar mass

Number of moles CH3COONa = 0.170 grams / 82.0 g/mol

Number of moles = CH3COONa = 0.00207 moles

Step 5: Calculate molarity

Molarity = moles / volume

Molarity solution = 0.00207 / 0.000917 L

Molarity solution = 2.26 mol/L = 2.26 M

The molarity of this solution is 2.26 M (option D)

6 0

2 years ago

Calculate the number of grams of sulfuric acid in 1 gallon of battery acid if the solution has a density of 1.31 g/ml and is 37.

adoni [48]

We know that density is equal to mass divided by volum, D=M/V and in this case we have 1 gallon of a solution of sulfuric acid with 37.4% of concentration in mass. 1 gallon is 3785.41 ml and according the formula M=D*V = 1.31 * 3785.41 = 4958.89 grams of solution. Only 37.4% of the solution is sulfuric acid, that is 4958.89 * 37.4/100= 1854.62 grams Then the number of grams of sulfuric acid is 1854.62 gr.

7 0

2 years ago

On the graph, indicate the distance that corresponds to the bond length of the N2 molecule by placing an X on the horizontal axi

Brut [27]

Answer:

Check the image in the file attached below.

Explanation:

The objective of this question is to use the diagram provided to indicate the distance that corresponds to the bond length of the N2 molecule by placing X on the horizontal axis.

The bond length shows the distance of the bonds between the nuclei of the bonded atoms between the N2 molecule and O2 molecule. From the diagram, we can see that the bond length of O2 shows a greater tendency over the N2 molecule and it also have higher potential energy than the N2 molecule.

6 0

2 years ago

Assuming that light is composed of particles (photons), how do you think you can adjust the conditions in the simulation to make

andreyandreev [35.5K]

Um I’m not sure what your trying to ask luv

5 0

2 years ago