S3: Chemistry - End of Trimester III Exam June 2024

What are components of a chemical reaction?

• Reactants and products
• Products and heat

• Heat and water

• Reactants and water

State the law of conservation of mass.

• Matter is neither created nor destroyed

• Matter can be created

• Matter can be destroyed

• Matter can be created and destroyed

What is the difference between exothermic reaction from endothermic reaction?

• Exothermic is hot while Endothermic is cold

• Exothermic is cold while Endothermic is hot

What is neutralization reaction ?

• Reaction between hydrogen and oxygen

• Reaction between oxidant and reductant

• A chemical reaction between salt and water.

• A chemical reaction between an acid and a base

Define a Redox reaction as applied in chemistry.

• Reduction and Oxidation reactions happen simultenously

• reduction of metals

• oxidation of non-metaks

What´s a combustion reaction in chemistry?

• Burning of something in presence of oxygen

• rusting reaction

• freezing reaction that absorbs energy

Balance the following chemical equations. __Fe + __Cl₂ → __FeCl₃

• 2Fe + 3Cl₂ → 2FeCl₃

• 3Fe + 2Cl₂ → 3FeCl₃

• 3Fe + 4Cl₂ → 3FeCl₃

• 1Fe + 2Cl₂ → 1FeCl₃

Balance the following chemical equations.

Zn + _HCl → ZnCl₂ + H₂

• 2

• 1

• 3

• 4

Balance the following chemical equations.

_Fe + _O₂ → _Fe₂O₃

• 4Fe + 3O₂ → 2Fe₂O₃

• 2Fe + 3O₂ → 2Fe₂O₃

• 2Fe + 2O₂ → 2Fe₂O₃

• Fe + O₂ → Fe₂O₃

Define an ionic bond

• sharing of electrons between atoms

• between two non-metals

• formed between a metal and a non-metal.

• is only found in metal atoms