A type of reaction where a reactant compound breaks down into two or more products.

A ratio can be used to determine the size of one quantity in relation to another.

The molar ratio of the reactants and products in a chemical reaction.

1 mole of a substance is 6.02 × 10²³ particles of it. The mass of a mole of a substance is its relative mass in grams.

A reaction using a symbol equation with coefficients to ensure there are equal numbers of atoms of each element on both sides of the equation.

Determining an equation experimentally: sodium hydrogencarbonate

Combined science

Three types of chemical reaction

Conservation of mass

Balancing equations

The mole

Moles and masses

Empirical formula calculations: using moles

Uncertainties in measurements: chemistry

Representations of a mole

Mass in a chemical reaction: using moles

Limiting reactants

Deducing an empirical formula experimentally: using moles

Determining an equation from given values

In the Making salts unit, pupils will learn about the production of pure salts, concentration and strength of acids, and what makes acids acidic and how bases can neutralise them.

In the Understanding Chemical Reactions unit, pupils learned about how atoms rearrange during chemical reactions and the conservation of mass.

This unit covers writing chemical formulae, balancing equations, and using the conservation of mass. It includes calculating moles, empirical formulae, relative formula masses, and theoretical yields. Emphasis is on stoichiometry, concentration, gas volumes, and using standard form.

Calculations involving masses

Physical activity and equipment requiring safe use

A reaction where a reactant breaks down into two or more products.

The mass of the reactants equals the mass of the products.

Ratio of particles that react/form in a chemical reaction.

Match the following key terms to their definition.

When sodium hydrogen carbonate is heated in a crucible it {{}} into sodium oxide, carbon dioxide and water.

Carbon dioxide is made during the reaction.

Why can the crucible lid remain closed during the following reaction?
2NaHCO₃ → Na₂O + 2CO₂ + H₂O.

5.0 g of sodium hydrogen carbonate was heated in a crucible. At the end of the reaction, 2.3 g of solid remained. Calculate the mass of gaseous products produced during the reaction. 

Which of the following is the balanced symbol equation for the thermal decomposition of sodium hydrogen carbonate into sodium hydroxide and carbon dioxide?

Calculate the maximum mass of sodium hydroxide (NaOH) that can be formed from 2.00 g of sodium hydrogen carbonate during the following reaction: 
NaHCO₃ → NaOH + CO₂
RFM: NaHCO₃ = 84; NaOH = 40.

The ratio of hydrogen to oxygen is 3 : 1.

The formula for sodium hydrogen carbonate is NaHCO₃. 
Which of the following statements about sodium hydrogen carbonate are correct?

What is the ratio of sodium hydrogen carbonate to water in the following equation?
2NaHCO₃ → Na₂O + 2CO₂ + H₂O.

Which of the following equations shows the correct relationship between moles, mass and relative mass?

What type of reaction does the following chemical equation represent?
CuCO₃ → CuO + CO₂.

Calculate the relative formula mass of sodium hydrogen carbonate, NaHCO₃. 
Relative atomic masses: Na = 23; H = 1; C = 12; O = 16.

Calculate the mole sof 4.2 g of sodium hydrogen carbonate, NaHCO₃. 
Relative formula mass of NaHCO₃ = 84.

Determining an equation experimentally: sodium hydrogencarbonate

Lesson outcome

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