Unit 4: Stoichiometry

Question 1

Use the symbols of the elements and write the
formulae of simple compounds
3 Deduce the formula of a simple compound from
the relative numbers of atoms present
4 Deduce the formula of a simple compound from
a model or a diagrammatic representation
5 Construct and use word equations
6 Interpret and balance simple symbol equations

Question 2

Determine the formula of an ionic compound
from the charges on the ions present

Question 3

Construct and use symbol equations, with state
symbols, including ionic equations
8 Deduce the balanced equation for a chemical
reaction, given relevant information

Question 4

Define relative atomic mass, Ar

Answer 4

The average mass of naturally occurring atoms of an element on a scale where the 12C atom has a mass of exactly 12 units, denoted as A_r

Question 5

Define relative molecular mass, Mr

Answer 5

The sum of the relative atomic masses (relative formula mass or Mr will be used for ionic compounds)

Question 6

Define the mole…

Answer 6

…in terms of a specific number of particles called Avogadro’s constant

Question 7

Use the molar gas volume, taken as 24dm3 at room temperature and pressure

Question 8

Calculate stoichiometric reacting masses, volumes of gases and solutions, and concentrations of solutions expressed in g /dm3 and mol/dm3 . (Calculations involving the idea of limiting reactants may be set.)

Question 9

For this unit dont use flashcards, revise with the booklet exercises and these notes: https://docs.google.com/document/d/1rD5S7qX3JbPcSKLaM7iIMhM4GSuB-Wxc9fwrW4u6D84/edit