No student devices needed. Know more
20 questions
In a chemical change, new substances are formed, for example
burning of wood
heating glass and bending it
boil water
melting an ice
iron + sulfur --> iron sulfide
from that word equation, the reactant(s) is/are ....
iron
sulfur
iron and sulfur
iron sulfide
when something burns, it reacts with the .... in the air
CO2
CO
O2
C
In burning Magnesium ribbon, do not look directly at the flame. Because
it can burn our eyes
it can melt our eyes
Magnesium burns very brightly and the light could harm our eyes
it can warm our eyes
When magnesium reacts with hydrochloric acid, gas are given off. The gas is .......
Oxygen
Hydrogen
Carbon dioxide
Carbon monoxide
When the hydrogen pops, it is reacting with oxygen to form .....
water
gas
ash
pop
zinc +sulfuric acid ---> ....... + hydrogen
zincate
zinc acid
zinc sulfate
sulfate
Copper carbonate + hydrochloric acid --->
Copper chloride + water + carbon dioxide
Copper chloride
water
carbon dioxide
What happens in a chemical reaction?
Atoms form new combinations
Atoms do not form new combinations
In detecting chemical reactions, there are few clues we can look, except ...
A colour change
A gas is given off
Heat is produced
No new substances
........ is formed when iron reacts with oxygen in the air
iroxy
rust
crumble
substances
from this experiment, we can conclude that rusting need
oxygen
water
oil
oxygen and water
how can iron be protected?
by painting it
by drowning it
by blowing it
by throwing it
melting chocolate is example of
chemical change
physical change
Baking a cake is example of
Chemical change
Physical change
The chemical symbol for magnesium is
Mg
mg
MG
Mag
The compound formed when magnesium reacts with oxygen is
Magnesium oxide
Magnesiumide
Magnesium oxygen
Oxymagnesium
How do we test a chemical substance is an acid?
litmus red turns blue
litmus blue turns red
litmus blue turns orange
litmus red turns purple
the chemical name for rust is
Fero
Iron(III) oxide
rusting
Iron man
acid + base -->
salt + water
oxygen
salt
water
Explore all questions with a free account