Understanding chemical reactions · Year 8 Chemistry
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In your construct
Question
When a substance changes from a solid to a liquid, it is called __________.
Characteristics of chemical reactions
Short answer
Year 8
1
No diagram
Which of the following is an example of a chemical change?
Characteristics of chemical reactions
Multiple choice
Year 8
1
No diagram
A __________ change is one that does not produce new substances and can often be reversed.
Characteristics of chemical reactions
Short answer
Year 8
1
No diagram
Which of the following represents a physical change?
Characteristics of chemical reactions
Multiple choice
Year 8
1
No diagram
What is the main difference between a physical change and a chemical change?
Characteristics of chemical reactions
Multiple choice
Year 8
1
No diagram
An __________ is a substance made of one type of atom.
Characteristics of chemical reactions
Short answer
Year 8
1
No diagram
What is a chemical reaction?
Characteristics of chemical reactions
Multiple choice
Year 8
1
No diagram
Where are products found in a chemical equation?
Characteristics of chemical reactions
Multiple choice
Year 8
1
Diagram
What do bubbles indicate in a chemical reaction?
Characteristics of chemical reactions
Multiple choice
Year 8
1
No diagram
Which observation(s) always indicate a chemical reaction has taken place?
Characteristics of chemical reactions
Multiple choice
Year 8
1
No diagram
__________ are the elements or compounds before a reaction takes place.
Characteristics of chemical reactions
Short answer
Year 8
1
No diagram
Most chemical reactions can be classed as __________ reactions, because the reaction occurs in one direction only (where the reactants are converted into the products).
Characteristics of chemical reactions
Short answer
Year 8
1
No diagram
What is a molecule?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
In a chemical reaction, the substances formed are called __________.
Conservation of mass and balanced symbol equations
Short answer
Year 8
1
No diagram
Which of the following is a compound?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
What happens to atoms during a chemical reaction?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
What is the chemical formula for carbon dioxide?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
A chemical symbol __________ is a representation of a chemical reaction using the symbols of the elements involved.
Conservation of mass and balanced symbol equations
Short answer
Year 8
1
No diagram
What does the arrow in a chemical equation represent?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
Diagram
Which of the following statements about the mass of reactants and products in a chemical reaction is correct?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
What is a word equation?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
Why must symbol equations be balanced?
Conservation of mass and balanced symbol equations
Multiple choice
Year 8
1
No diagram
A __________ represents a substance using element symbols and the number/ratio of atoms of each element in the substance.
Conservation of mass and balanced symbol equations
Short answer
Year 8
1
No diagram
To balance a chemical equation, you need to change the __________ in front of the chemical formulas to ensure there are equal numbers of atoms of each element on both sides of the equation.
Conservation of mass and balanced symbol equations
Short answer
Year 8
1
No diagram
Which of the following best describes an element?
Chemical reactions: oxidation
Multiple choice
Year 8
1
No diagram
What happens to the total mass of substances during a chemical reaction?
Chemical reactions: oxidation
Multiple choice
Year 8
1
No diagram
Match the following terms with their definitions:
Chemical reactions: oxidation
Matching
Year 8
4
No diagram
A __________ is a substance made of two or more elements chemically bonded.
Chemical reactions: oxidation
Multiple choice
Year 8
1
No diagram
Why is it important to follow safety protocols in the laboratory?
Chemical reactions: oxidation
Multiple choice
Year 8
2
No diagram
A __________ change results in the formation of new substances with different chemical properties, such as burning or rusting.
Chemical reactions: oxidation
Short answer
Year 8
1
No diagram
In an oxidation reaction involving magnesium and oxygen, which of the following is a correct product?
Chemical reactions: oxidation
Multiple choice
Year 8
1
No diagram
What are the three necessary components for combustion to occur?
Chemical reactions: oxidation
Multiple choice
Year 8
3
No diagram
__________ is a type of reaction in which oxygen bonds to elements of the reactants.
Chemical reactions: oxidation
Short answer
Year 8
1
No diagram
What is rusting?
Chemical reactions: oxidation
Multiple choice
Year 8
1
No diagram
An oxide is a compound containing __________ that is formed during an oxidation reaction.
Chemical reactions: oxidation
Short answer
Year 8
1
No diagram
Match the key words to their definitions:
Chemical reactions: oxidation
Matching
Year 8
3
No diagram
Combustion requires fuel, __________, and an initial source of energy, usually heat, to start the reaction.
Chemical reactions: combustion
Short answer
Year 8
1
No diagram
Match the states of matter with their characteristics:
Chemical reactions: combustion
Matching
Year 8
3
No diagram
During a chemical reaction, the total mass of the reactants __________ the total mass of the products.
Chemical reactions: combustion
Short answer
Year 8
1
No diagram
When atoms of different elements bond together, they form a __________.
Chemical reactions: combustion
Short answer
Year 8
1
No diagram
CO₂ contains carbon and oxygen atoms. Which of the following chemicals also contain both carbon and oxygen atoms?
Chemical reactions: combustion
Multiple choice
Year 8
2
No diagram
Match up the word equations for the oxidation reactions:
Chemical reactions: combustion
Matching
Year 8
6
No diagram
What is combustion?
Chemical reactions: combustion
Multiple choice
Year 8
1
No diagram
Burning is a type of combustion where substances react with oxygen and produce visible __________.
Chemical reactions: combustion
Short answer
Year 8
1
No diagram
Which of the following is often formed in chemical reactions if oxygen and carbon atoms are present?
Chemical reactions: combustion
Multiple choice
Year 8
1
No diagram
__________ is often formed in chemical reactions if oxygen and hydrogen atoms are present.
Chemical reactions: combustion
Short answer
Year 8
1
No diagram
A __________ is a substance that releases stored energy during combustion.
Chemical reactions: combustion
Short answer
Year 8
1
No diagram
When there is limited oxygen present during a combustion reaction, carbon monoxide will be produced (not carbon dioxide). What is the formula for carbon monoxide?
Chemical reactions: combustion
Multiple choice
Year 8
1
No diagram
What are common signs that a chemical reaction is taking place?
Chemical reactions: decomposition
Multiple choice
Year 8
3
No diagram
In a chemical reaction, what happens to the atoms of the reactants?
