WorksheetsChemical Changes
Total questions: 47
Worksheet time: 29mins
A granular substance is added to a liquid. Which of the following would provide evidence to suggest a chemical change has taken place?
The liquid gives off heat.
The granules dissolve completely.
The volume of the liquid increases.
The granules seem to get smaller.
All of the following are evidence of a chemical change EXCEPT -
change in state of matter.
formation of a gas.
color change.
precipitate forms.
Which of the following situations provides evidence that a chemical change has taken place?
Water, when boiled, evaporates and turns into vapor.
Sugar, when added to iced tea, dissolves into the liquid.
Two liquids are mixed, and a solid substance forms.
A piece of paper is cut into many small pieces.
Which of the following would indicate the formation of a new substance?
A liquid turns to a solid
A sample of metal melts
Bubbles and fizzing occur
A solid dissolves in a liquid
Four substances were mixed with a clear liquid. The observations are recorded in the following table. Based on the observations, for which mixture is there best evidence that a new substance was formed?
Substance 1
Substance 2
Substance 3
Substance 4
A student notices that sugar, when heated over a flame, turns black. How does the student know that a new substance is being formed?
A temperature of the sugar increases.
The color of the sugar changes to black.
Sugar began to melt within the test tube.
Sugar started as white crystals.
Which symbol shows a chemical reaction has occured?
A
B
C
D
A physical change is the same as a chemical change
TRUE
FALSE
Identify the product(s) in this word equation
Sodium
Sodium chloride
Sodium and Chlorine
Sodium and sodium chloride
In a word equation the REACTANTS
Are written on the right hand side of the arrow
Are produced in a chemical reaction
Are always the same
Are the substances that react together
The products in this reaction are?
Two solids
One solid and one gas
Three solids and a gas
Two solids and a gas
The new substances formed in a chemical reaction are called
Reactants
Atoms
Products
Reagents
What are the reactants in this word equation?
Carbon dioxide and oxygen
Carbon dioxide and water
Oxygen and glucose
Oxygen and water
In a chemical reaction...
New atoms are created
Atoms rearrange
Atoms are destroyed
Nothing Happens
In this chemical reaction zinc is a...
Product
Reactant
Neither
Magneisum reacts with oxygen to form magnesium oxide. The correct word equation is...
A
B
C
D
Which of the following values would represent the pH of a strong base?
1
8
7
13
Which of the following is NOT a characteristic of an acid?
sour taste
corrosive
turns litmus paper blue
neutralises bases
A substance that is 3 on the pH scale would be a(n):
acid
base
neutral
solute
Which of the following is a neutralisation reaction?
metal + acid → salt + hydrogen
metal + acid → salt + water
carbonate + acid → salt+ carbon dioxide + hydrogen
base + acid → salt + water
Acid rain is caused by
pollutants in the air such as SO2 and NO2 reacting with oxygen
acids in the rain reacting with rocks containing carbonates
pollutants in the air such as SO2 and NO2 reacting with water
global warming, heating the earth's atmosphere
An alkali is produced when
A salt dissolves in water
A base dissolves in water
An acid dissolves in water
An acid reacts with a base
Which of the following substances is alkaline
dishwashing liquid
vinegar
distilled water
milk
Indicators
have a very high pH
change colour to show the pH of a substance
change colour in the presence of salts
have a very low pH
If all three indicators were added to a mystery solution and it turned green, what pH is the solution likely to be
2 - 4
4 - 7
7 - 9
9 - 11
If you added universal indicator to hydrochloric acid, what colour would it turn
blue
green
yellow
red
What pH is the strongest base?
1
7
4
14
Iron rusts in the presence of:
Vacuum
Moisture
Oxygen
Moisture and Oxygen
Galvanisation of iron and steel involves:
Plating with a more reactive metal, like zinc, that forms a thin protective layer
applying a layer of paint to protect the metal from rusting
annealing the metal to make it stronger
covering with a plastic layer to protect the metal from rusting
Is this an example of corrosion or combustion?
corrosion
combustion
What conditions are required for rusting?
water only
oxygen only
water and oxygen
Why is rusting a problem?
It looks ugly, no one likes orange
It makes iron really bendy
It makes iron lose its strength
Look at the picture. From what you see, choose which things are needed for rusting to occur.
water only
oxygen only
oil and water
water and oxygen
Do all metals corrode?
Yes
No
Which of the following items will rust?
A plastic bottle
A gold ring
An iron bridge
A cardboard box
In a word equation the REACTANTS
Are written on the right hand side of the arrow
Are produced in a chemical reaction
Are always the same
Are the substances that react together
The new substances formed in a chemical reaction are called
Reactants
Atoms
Products
Reagents
