WorksheetsY7 U8 Changes to Materials
Total questions: 70
Worksheet time: 50mins
Which of these is an example of a physical change?
Toast burning
An egg cooking
Ice melting
Car rusting
Which of these could be evidence of a physical change?
Colour changed
Change is irreversible
Explosion
Change is easily reversible
Gas test for oxygen is....
A lit splint makes a pop sound
A glowing splint relights
Limewater goes cloudy
We can breathe it
Gas test for carbon dioxide is....
A lit splint makes a pop sound
A glowing splint relights
Limewater goes cloudy
We can't breathe it
Gas test for hydrogen is....
A lit splint makes a pop sound
A glowing splint relights
Limewater goes cloudy
It smells bad!
In the chemical reaction shown, what are the products?
copper sulfate, magnesium, magnesium sulfate and copper
copper sulfate and magnesium
magnesium sulfate and copper
Copper is the only product
In this reaction, the copper sulfate and the magnesium are called the...
Producers
Reactants
Starters
Reactors
What is the meaning of the arrow in the middle of a word equation? Choose the BEST description.
"combine to make"
"equals"
"goes to"
"react to form"
Magnesium chloride is a salt with similarities to table salt (sodium chloride). One way to make magnesium chloride is simply to react two elements together.
What is the name of the element missing from the word equation? (Take care with spelling.)
(a)
During a chemical reaction, bubbles may be formed. This shows that at least one of the products of this reaction is a (a)
What risk is associated with this bottle of dilute sulfuric acid?
It may irritate skin or eyes, causing pain or a rash
It may catch fire easily
It may cause severe skin burns
If it touches you it may cause damage to your nervous system
How many TOTAL atoms are in the chemical formula shown? CuSO4
6
7
5
3
How many TYPES of atoms are in the chemical formula shown? CuSO4
3
4
2
1
When zinc burns in oxygen it forms:
zinc oxide
zinc hydroxide
zinc carbonate
zinc dioxide
What pH represents acids?
0-6
7
8-14
0-14
What pH represents alkalis?
0-6
7
8-14
0-14
What pH represents a neutral solution?
0-6
7
8-14
0-14
Combustion is another name for
burning
thermal decomposition
neutralisation
What colour does universal indicator turn to indicate a substance is strongly acidic?
red
orange
blue
purple
What colour does universal indicator turn to indicate a substance is strongly alkaline?
red
orange
blue
purple
Sodium hydroxide is a/an
acid
alkali
salt
Repeating an experiment several times will make the experiment
More reliable
Less reliable
More precise
Less precise
Which is a neutraisation reaction?
acid + alkali → salt + water
acid + metal → salt + hydorgen
acid + carbonates → salt + water + carbon dioxide
acid + lime water → salt + lime
In a word equation, the reactants are place on which side of the arrow?
on the right hand side
on the left hand side
some on the right hand side
some on the right hand side
In a word equation, the products are place on which side of the arrow?
on the right hand side
on the left hand side
some on the right hand side
some on the right hand side
What indicates a chemical reaction occurred?
heat or light is released
gas (bubbles) produced
color change
all of the above
Which of the following IS a physical change?
Getting a haircut
Iron going rusty
A compound forming
Milk going sour
How is a chemical change different from a physical change?
there is no difference
a physical change creates a new substance
a chemical change results in a new substance
Which of the following is evidence of a chemical reaction?
bubbles being produced
water changing to ice
saltwater
paper being cut in half
a copper penny turning greenish after a few years is a...
Chemical Change
Physical Change
A substance that is formed when two or more elements are chemically joined during a chemical reaction is a(n)...
Product
Compound
Molecule
Atom
Carbon is an example of an
element
compound
molecule
water is an example of a(n)
element
compound
atom
A chemical reaction could be identified by
a colour change
melting
evaporation
A chemical reaction could be identified by
bubbles being produced
melting
evaporation
condensation
A chemical reaction could be identified by
heat being given off
melting
evaporation
condensation
An element is:
carbon
water
carbon dioxide
methane
An element is:
copper sulfate
water
hydrogen
methane
An element is:
copper sulfate
water
oxygen
methane
A compound is:
CH4
O
H
Fe
A compound is:
H2O
O
H
Fe
A compound is:
Copper sulfate
Oxygen
Hydrogen
Iron
A compound is:
Copper
Oxygen
Hydrogen sulfide
Iron
Is an ice cream cone melting a physical or chemical change?
Physical
Chemical
The pH scale ranges from
1-7
0-14
0-20
1-14
A pH of 2 would be a
weak base
neutral
strong acid
weak acid
strong base
_____ has a neutral pH
Bleach
Water
Orange Juice
Blood
What colour will Litmus paper go when in contact with Hydrochloric acid?
Red
Green
Blue
Purple
How many atoms of Oxygen are in this compound?
CuSO4
1
3
4
6
How many atoms of Nitrogen (N) are in this compound?
KNO2
1
2
3
4
Does this picture represent element, compound, or mixture?
element
compound
mixture
Does this picture represent element, compound, or mixture?
element
compound
mixture
Elements contain ______ type of atom
one
two or more
large
mixture
In class, we built a water molecule with 2 hydrogens and 1 oxygen. Water is a...
element
compound
mixture
atom
Why is toothpaste alkaline?
It can neutralise strong alkaline in
your mouth
It can neutralise acid in
your mouth
It can refresh your teeth
Toothpaste is not alkaline.
What colour is Universal indicator when the solution is neutral?
Red
Green
Blue
Purple
What type of reaction occurs when you react an acid with an alkali?
combustion
decomposition
no reaction
neutralisation
Excess acids in stomach can be neutralized using ............
antacid
vinegar
slaked lime
hydrochloric acid
A molecule is
a singular particle of a particular element
another name for an element
2 or more atoms that are combined
This image shows a
chemical reaction
physical change
musical change
all of these answers are correct
During a chemical reaction, atoms can
be destroyed to form a new substance
be created to form a new substance
be rearranged to form a new substance
What are the atoms of each element in this chemical formula Na2SO4
2 Na, 0 S, 4 O
1 Na, 1 S, 4 O
1 Na, 4 S, 4 O
2 Na, 1 S, 4 O
magnesium + (a) → magnesium chloride + hydrogen
Which metal is the most reactive with water?
potassium
sodium
lithium
calcium
Where do we store metals that are very reactive to water?
(a)
