Question

1. a 25.0 l tank contains hydrogen (h₂) gas at a temperature of 149 k and a pressure of 1.51 atm. how many moles of hydrogen gas is in the tank? 2. when calculating ideal gas laws, which units do volume and temperature need to be? a) c b) v c) l d) ml

Explanation:

Step1: Identify the ideal - gas law formula

The ideal - gas law is $PV = nRT$, where $P$ is pressure, $V$ is volume, $n$ is the number of moles, $R$ is the ideal - gas constant ($R=0.0821\ L\cdot atm/(mol\cdot K)$), and $T$ is temperature.

Step2: Rearrange the formula to solve for $n$

We get $n=\frac{PV}{RT}$.

Step3: Substitute the given values

Given $P = 1.51\ atm$, $V=25.0\ L$, $T = 149\ K$, and $R = 0.0821\ L\cdot atm/(mol\cdot K)$. Then $n=\frac{1.51\ atm\times25.0\ L}{0.0821\ L\cdot atm/(mol\cdot K)\times149\ K}$.

Step4: Calculate the value of $n$

$n=\frac{37.75\ L\cdot atm}{12.2329\ L\cdot atm/mol}\approx3.09\ mol$.

For the second question:
When calculating ideal - gas laws, volume is typically in liters ($L$) and temperature is in Kelvin ($K$).

Answer:

1. $3.09\ mol$
2. C. L