Question

You are given 4.92 grams of H2O. How many moles is that?

Answer 1

0.273 mol H₂O

General Formulas and Concepts:

Chemistry - Atomic Structure

• Reading a Periodic Table
• Using Dimensional Analysis

Step-by-step explanation:

Step 1: Define

4.92 g H₂O

Step 2: Identify Conversions

Molar Mass of H - 1.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of H₂O - 2(1.01) + 16.00 = 18.02 g/mol

Step 3: Convert

`4.92 \ g \ H_2O((1 \ mol \ H_2O)/(18.02 \ g \ H_2O) )` = 0.27303 mol H₂O

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

0.27303 mol H₂O ≈ 0.273 mol H₂O