Question

New concept cars in the Detroit Auto Show feature engines that burn hydrogen gas in air to produce water vapor. Suppose that fuel tank contains 150. L of H2 gas at 20.0 atm pressure at 25.0˚C. If all of this gas is burned, what mass (in grams) of water vapor is produced?

Answer 1

247.2g

Step-by-step explanation:

Using the general gas law equation as follows:

PV = nRT

Where;

P = pressure (atm)

V = volume (L)

n = number of moles (mol)

R = gas law constant (0.0821 Latm/molK)

T = temperature (K)

According to the information in this question, a fuel tank contains 150. L (V) of H2 gas at 20.0 atm (P) at 25.0˚C (T)

Temperature = 25°C = 25 + 273 = 298K

Using PV = nRT

20 × 150 = n × 0.0821 × 298

3000 = 24.4658n

n = 3000/24.4658

n = 122.62

n = 122.6mol

Using the formula, mole = mass/molar mass, to find the mass of H2 gas.

Molar mass of H2 = 1.008(2)

= 2.016g/mol

122.6 = mass/2.016

mass = 122.6 × 2.016

mass = 247.2g.