Question

A gas of 3.4 moles occupies a volume of 0.046 L at 298 K. What is the pressure in kPa?

a. 6.1 x 10^2 kPa
b. 9.45 x 10^-3 kPa
c. 4.40 x 10^5 kPa
d. 2.1 x 10^5kPa

Answer 1

The pressure of the gas is calculated using the ideal gas law. After substituting the given values into the equation and solving, the pressure is found to be approximately 4.45 × 10⁵ kPa, making option (c) 4.40 × 10⁵ kPa the correct answer.

Step-by-step explanation:

To determine the pressure of a gas given the moles, volume, and temperature, we use the ideal gas law, which is:

PV = nRT

Where:

• P = pressure of the gas
• V = volume of the gas
• n = number of moles of the gas
• R = ideal gas constant
• T = temperature in Kelvin

In this problem, we have:

• n = 3.4 moles
• V = 0.046 L
• T = 298 K

We will use the value of the ideal gas constant R when the pressure is measured in kPa, which is 8.314 kPa·L/(mol·K).

Substituting the values into the ideal gas law, we get:

P = (nRT)/V

P = (3.4 moles × 8.314 kPa·L/(mol·K) × 298 K) / (0.046 L)

P = 204790.944 kPa / 0.046 L

P = 4.45 × 10⁵ kPa

Thus, the correct answer is (c) 4.40 × 10⁵ kPa.

Answer 2

Answer : The correct option is,
`2.1* 10^5kPa`

Explanation :

To calculate the pressure of gas we are using ideal gas equation as:

`PV=nRT`

where,

P = pressure of gas = ?

V = volume of gas = 0.046 L

n = number of moles of gas = 3.4

R = gas constant = 8.314 L.kPa/mol.K

T = temperature of gas = 298 K

Now put all the given values in the above formula, we get:

`P* (0.046L)=(3.4mol)* (8.314L.kPa/mol.K)* (298K)`

`P=1.83* 10^5kPa\approx 2.1* 10^5kPa`

Therefore, the pressure of gas is,
`2.1* 10^5kPa`