Question

How many moles of NH3 are there in a 95.5 L sample?

Answer 1

`\boxed {\boxed {\sf 4.26 \ mol \ NH_3}}`

Step-by-step explanation:

This question asks us to convert liters to moles. We know that 1 mole of any gas contains 22.4 liters. This includes ammonia (NH₃), so let's set up a ratio.

`( 1 \ mol \ NH_3)/( 22.4 \ L \ NH_3)`

Since we are converting 95.5 liters of ammonia to moles, we multiply by that value.

`95.5 \ L \ NH_3 *( 1 \ mol \ NH_3)/( 22.4 \ L \ NH_3)`

The units of liters of ammonia (L NH₃) cancel.

`95.5 *( 1 \ mol \ NH_3)/( 22.4 )`

Condense into 1 fraction.

`(95.5)/(22.4 ) \ mol \ NH_3`

Divide.

`4.26339285714 \ mol \ NH_3`

The original measurement of liters (95.5) has 3 significant figures. Our answer must have the same. For the number we calculated, that is the hundredth place.

The 3 in the thousandth place (4.26339285714) tells us to leave the 6 in the hundredth place.

`4.26 \ mol \ NH_3`

95.5 liters of ammonia is equal to 4.26 moles of ammonia.