Question

Select the correct answer. An adult human lung has a volume of 2.9 liters. If its volume decreases to 1.2 liters and it contains 0.049 mole of air after it exhales, how many moles of air does it contain when full? A. 0.025 mol B. 0.041 mol C. 0.083 mol D. 0.12 mol E. 0.14 molThomas has 235 grams of K2S in the chemistry lab. How many atoms of potassium (K) are in 235 grams of the compound?

Answer 1

Answer:

Answer:- The lung contains 0.12 moles of air when it's full.

Solution:- At constant temperature and pressure, the volume is directly proportional to the moles of the gas.

\frac{V_1}{V_2}=\frac{n_1}{n_2}V2V1=n2n1

where, V_1V1 and V_2V2 are the initial and final volumes. Similarly, n_1n1 and n_2n2 are the initial and final moles of the air.

Let's plug in the given values in the formula and solve this for initial moles of the gas.

\frac{2.9L}{1.2L}=\frac{n_1}{0.049mol}1.2L2.9L=0.049moln1

n_1=\frac{2.9L(0.049mol)}{1.2L}n1=1.2L2.9L(0.049mol)

n_1=0.12moln1=0.12mol

So, the lung contains 0.12 moles of air when it's full.