Chapter 10 - The Mole

Study Guide

Compound that has a specific number of water molecules bound to its atoms

hydrate

Percent by mass of each element in a compound

Percent composition

Mass in grams of one mole of any pure substance

Molar mass

Formula of a compound with the smallest whole-number mole ratio of the elements

Empirical formula

Specifies the actual number of atoms of each element in one molecule of a compound

Molecular formula

SI base unit used to measure the amount of a substance

mole

6.02 × 10^23

Avogadro's number

The SI unit of molar mass

g/mole

How many moles of oxygen atoms do 1.5 moles of CO2 contain?

3.0 mol

Counting units include…

Dozen, pair, mole

There are 6.02 × 10^23 atoms in a

mole

How many moles are in 3.01 × 10^23 molecules of water (H₂O)?

0.5 mole

How many molecules are in 2.50 moles of water (H₂O)?

1.51 x 10^24 molecules

Water (H₂O) is composed of hydrogen and oxygen atoms. Calculate the molar mass of water using the atomic masses: Hydrogen (H) = 1.008 g/mol, Oxygen (O) = 16.00 g/mol

18.02 g/mol

A chemist has 10 moles of silver (Ag). How many grams of silver are present in the sample? (Use the molar mass of silver: 107.87 g/mol.)

1078.7g

A sample contains 3.01 × 10^23 atoms of iron (Fe). What is the mass of the sample in grams? (Use the molar mass of iron: 55.85 g/mol, and Avogadro's number: 6.022 × 10^23 atoms/mol.)

27.925 g

How many moles of oxygen are in 1 mole of H2CrO4?

4 moles

How many moles of oxygen are there in 3.0 moles of Al2O3?

9 moles

What is the mass of 2 moles of H2O?

36.032g