Question

How many moles of H2O are in 4.00 L of water?

Answer 1

Answer:

0.179 mol H₂O

Explanation:

STP - 1 atm, 0°C

Assuming we're in STP:

Step 1: Find conversions

1 mol = 22.4 L at STP

Step 2: Use Dimensional Analysis

$4.00 \hspace{3} L \hspace{3} H_2O(\frac{1 \hspace{3} mol \hspace{3} H_2O}{22.4 \hspace{3} L \hspace{3} H_2O} )$ = 0.178571 mol H₂O

Step 3: Simplify

We have 3 sig figs.

0.178571 mol H₂O ≈ 0.179 mol H₂O