HSC Chemistry Questions and Answers.

HSC Chemistry Questions and
Answers.

Combustion reaction - CORRECT ANSWER The process of burning
something. The reaction between a substance and oxygen which then
transfers energy to the surroundings as light and heat.

Combination reaction - CORRECT ANSWER A chemical change in which two or more
substances react to form a single new substance.
Example: A + B --> AB

Decomposition reaction - CORRECT ANSWER A chemical change in which a single
compound is broken down into two or more simpler products.
Example: AB --> A + B

Single displacement reaction - CORRECT ANSWER A chemical reaction in which one
element replaces another element in a compound.
Example: A + BC --> B + AC

Double displacement reaction - CORRECT ANSWER A chemical reaction where two
compounds react, and the positive ions (cation) and the negative ions (anion) of the two
reactants switch places, forming two new compounds or products.
Example: AB + CD --> AD + CB

Redox reaction - CORRECT ANSWER A chemical reaction involving the transfer of one
or more electrons from one reactant to another.

Oxidation - CORRECT ANSWER The process or result of oxidizing or being oxidized by
the loss of electrons from a substance involved in a redox reaction.

Neutralisation reaction - CORRECT ANSWER A reaction of an acid with a base,
forming a salt and water.

Acid + Metal reaction - CORRECT ANSWER A reaction of an acid with a metal, forming
a salt and hydrogen gas.

Acid + Carbonate reaction - CORRECT ANSWER A reaction of an acid and a
carbonate, forming a salt, water and carbon dioxide.

Alkane - CORRECT ANSWER A hydrocarbon containing only single carbon-carbon
covalent bonds. Example: butane (suffix: -ane)

, Alkene - CORRECT ANSWER A hydrocarbon containing at least one carbon-carbon
double bond. Example: propene (suffix: -ene)

Alkyne - CORRECT ANSWER A hydrocarbon containing at least one carbon-carbon
triple bond. Example: propyne (suffix: -yne)

Alcohol - CORRECT ANSWER A hydrocarbon containing a hydroxl group (OH).
Example: hexanol (suffix: -anol)

Carboxylic acid - CORRECT ANSWER A hydrocarbon containing a carboxyl group (-
COOH). Example: butanoic acid (suffix: -anoic acid)

Ester - CORRECT ANSWER A hydrocarbon, synthesised by reacting a carboxylic acid
& and alcohol; containing a (-CO-O-) functional group. Example: pentyl ethanoate
(suffix: -yl -ate/-oate)

Buffer - CORRECT ANSWER A compound that can prevent sharp, sudden changes in
pH.

Equilibrium - CORRECT ANSWER A state of balance among the components of a
system.

Factors that affect equilibrium - CORRECT ANSWER Effect of temperature,
concentration, pressure and/or volume on a system.

Le Chatelier's principle - CORRECT ANSWER This principle suggests when stress is
applied to a system at equilibrium, the system changes to relieve the stress

Reversible reaction - CORRECT ANSWER A chemical reaction in which the products
re-form the original reactants.

Irreversible reaction - CORRECT ANSWER A chemical reaction where products cannot
revert back to reactants.

Static equilibrium - CORRECT ANSWER A condition where there are no net external
forces acting upon a particle. At rest and stationary.

Dynamic equilibrium - CORRECT ANSWER A state of balance between continuing
processes.

Open system - CORRECT ANSWER A system in which matter can enter from or
escape to the surroundings.

Closed system - CORRECT ANSWER A system in which no matter is allowed to enter
or leave.