FUN WITH REACTIONS

A chemical equation is a statement that describes a chemical change in terms of

• symbols and formulae

• energy

• number of atoms

• colours

Reactants are placed on __________ side of the reaction

• right

• left

identify the correct molecular formula of sulphuric acid

• HCL

• HNO3

• H2O

• H2SO4

An ion with positive charge is called ____________

• cation

• anion

• electron

• none of the above

Identify the correct valency of calcium

• 1

• 2

• 3

• 0

which of the following has valency 4?

• magnesium

• carbon

• oxygen

• hydrogen

metals have ___________ valency

• positive

• negative

• both positive and negative

• none of the above

Identify the correct balanced reaction of the following.

• H₂ + O_{2 ------} H₂ O

• 2H₂ + O_{2 ------} H₂ O

• 2H₂ + O_{2 ------} 2 H₂ O

• H₂ + O_{2 ------} H₂ O₂

This gas has a rotten egg smell

• ammonia

• hydrogen sulphide

• hydrogen

• oxygen

Identify the correct symbolic representation equation for the following:

Iron sulphide + hydrochloric acid ----------- Iron (II) chloride + hydrogen sulphide

• FeS + HCl ----------- Fe (Cl)₂ + H₂S

• FeS + HCl ----------- Fe (Cl)₃ + H₂S

• FeS + HCl ----------- Fe (Cl) + HS