WorksheetsChemical Reactions Exercises
Total questions: 20
Worksheet time: 10mins
Which of the following materials undergoes a chemical change?
Cutting of stainless metal plates
Crushing chunks of ice
Dissolving sugar in water
Rotting of tomatoes
What are the substances that are present before a chemical reaction occurs?
Coefficients
Products
Reactants
Subscripts
Which symbol in a chemical equation represents "yields" or "produces"?
+
→
=
↑
Which of the following is NOT an evidence of a chemical reaction?
Change in temperature
Evolution of gas
Melting of ice
Formation of precipitate
What law states that matter cannot be created nor destroyed in a chemical reaction?
Law of Conservation of Mass
Law of Definite Proportions
Law of Multiple Proportions
Law of Chemical Change
What happens to the mass of reactants and products in a chemical reaction?
The mass of products is greater.
The mass of reactants is greater.
They must be equal.
There is no relationship.
What happens when quicklime (CaO) is mixed with water?
Change in temperature
Formation of bubbles
Evolution of light
Production of mechanical energy
In the chemical equation H2 + O2 → H2O, what are the products?
H2 and O2
O2 and H2O
H2O
H2
Which of the following best describes a combustion reaction?
A reaction where two elements combine to form a new product
A reaction where oxygen reacts with a hydrocarbon to form carbon dioxide and water
A reaction where a compound breaks down into simpler substances
A reaction where ions are exchanged between two reactants
Which type of reaction is represented by AB → A + B?
Combination
Decomposition
Single replacement
Double replacement
If sodium bicarbonate (baking soda) is added to vinegar, what type of reaction takes place?
Single replacement
Acid-base reaction
Double replacement
Decomposition
What happens if you mix a hydrochloric acid solution with a sodium hydroxide solution?
A neutralization reaction occurs, forming water and salt
A decomposition reaction occurs, forming hydrogen gas
A combustion reaction occurs, forming carbon dioxide
A synthesis reaction occurs, forming acid and base
A student observes a chemical reaction in which a gas is produced, a solid precipitate forms, and the temperature increases. What type of reaction likely occurred?
Combustion
Neutralization
Decomposition
Single replacement
In the reaction Zn + CuSO4 → ZnSO4 + Cu, which element is being displaced?
Zn
Cu
SO4
O2
Which of the following best explains why a burning candle is both a physical and chemical change?
Only the wick undergoes a chemical change.
The melting of wax is a chemical change, and the burning of wax is a physical change.
The burning of wax is a chemical change, and the melting of wax is a physical change.
Both the burning and melting of wax are physical changes.
A chemical equation must always be balanced to follow the Law of Conservation of Mass.
True
False
A double replacement reaction occurs when an element replaces another element in a compound.
True
False
An increase in temperature is always a sign of a chemical reaction.
True
False
A precipitate forms when a solid is produced in a chemical reaction.
True
False
The formation of bubbles when vinegar is mixed with baking soda indicates the evolution of a gas.
True
False
