GRADE 9 NATURAL SCIENCE EXAM QUESTIONS AND WITH COMPLETE ANSWERS

GRADE 9 NATURAL SCIENCE EXAM
QUESTIONS AND CORRECT ANSWERS
What happens if you burn a piece of wood with oxygen ? - ANSWER-- it combines with
oxygen
- changes colour
- carbon dioxide and water vapor is released
- gases floats into the air

What is combustion? - ANSWER-the process of burning something

Compound - ANSWER-A substance made up of two or more different elements joined
by chemical bonds

How to neutralize something ? - ANSWER-Use a weak acid to neutralize bases

properties of bases - ANSWER-taste bitter
slippery to the touch
can be poisonous & corrosive
release OH- ions in water

properties of acids - ANSWER-- sour taste
- turn blue litmus paper red, keep red litmus paper red
- ph < 7
- feels rough

Balancing Equations - ANSWER-The mass and the charge are balanced on both sides
of the reaction

What is a group? - ANSWER-Vertical column in the periodic table

What is a period? - ANSWER-horizontal row in the periodic table

Reactions - ANSWER-in reaction, energy is released or absorbed

Neutralization - ANSWER-A reaction between an acid and a base

Rusting - ANSWER-happens when metal reacts to oxygen

Nucleon - ANSWER-protons, neutrons and electrons

Sodium - ANSWER-Na

carbon dioxide - ANSWER-CO2