NEW
Font size
WorksheetsG6 revision: Chemical reactions
Total questions: 20
Worksheet time: 14mins
A chemical change is different than a physical change because in a chemical change...
Chemicals are used
Molecules do not physically touch
A new substance is formed and in a physical change no new substance is formed
The change can be seen but in a physical change it cannot
In a chemical reaction...
The atoms of the reactants always stay together to form the products
The atoms of the reactants unbond, rearrange, and then rebond to form the products
New atoms are formed which combine to make the products
Some atoms disappear while others multiply to form the products
In a chemical reaction, mass is conserved. This means that
The mass of the products stays the same during a chemical reaction
The mass of the products is always twice the mass of the reactants
The mass of the reactants stays the same during a chemical reaction
The type and number of atoms in the reactants equals the type and number of atoms in the products
The law of conservation of mass states
matter can not be created or destroyed
matter can be created and destroyed
matter can be changed and created
matter can be rearranged and destroyed
Increasing the amount of reactants may increase the amount of
atoms
matter
molecules
products
What is a sign of a physical change?
odor produced
change in state of matter
light
temperature change
What is a sign of a chemical change?
change in state of matter
change in size
change in shape
temperature change
Using the image above determine if a physical or chemical change has occurred in Model B.
A chemical change has occurred in model B. In the second cup you can see that the molecules have just rearranged.
A chemical change has occurred in model B. In the second cup you can see a bond (black line) has formed between the green and blue molecule and new light pink/light blue molecules have also formed.
A physical change has occurred in model B. In the second cup you can see that the molecules have just rearranged.
A physical change has occurred in model B. In the second cup you can see a bond (black line) has formed between the green and blue molecule and new light pink/light blue molecules have also formed.
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
Iron reacts with sulfur to produce iron(II) sulfide. Choose the correct word equation.
iron + solid → iron sulfide
iron + sulfur → iron sulfide
iron sulfide + iron→ sulfur
sulfur + iron sulfide → iron
Sodium reacts with chlorine to produce sodium chloride. Choose the correct word equation.
sodium chloride → chlorine + sodium
sodium + carbon dioxide → sodium carbonate
sodium + chlorine → sodium chloride
