Savvas Chemical Reactions

Lesson: Chemical Reactions

By William Lovering

Multiple Choice

One of the signs of a chemical reaction taking place is:

• Bubbles are produced 
• Reactants are not combining
• Products are not forming
• Color is not changing

Multiple Choice

Which of the following describes a precipitate?

• a liquid forms when a block of metal is heated
• a solid forms when one liquid is poured into another
• a gas forms when a solid is placed in a liquid
• bubbles form when an acid is poured on a rock

Multiple Choice

A clear liquid from a flask is poured into another clear liquid in a beaker. Which of the following results of this procedure would indicate a new substance was formed?

• The level of the substance in the beaker is higher after the other liquid is added.
• A yellow solid forms and then settles to the bottom of the beaker.
• Small white crystals are left behind in the flask that held the first liquid.
• The mass of the combined liquids is greater than either original liquid.

Multiple Choice

The word "yields" describing a chemical reaction means

• to make or create something

• combine in water

• causes a reaction to stop

• heat must be added

Multiple Choice

Each substance in a chemical reaction is called a

• reactant

• product

• species

• compound

Multiple Choice

Species in a chemical equation are separated by

• -->

• +

• (s)

• coefficient

Multiple Choice

What does the number ₃ represent in 4NH₃?

• Subscript

• Superscript

• Coefficient

Multiple Choice

What does the number 4 represent in 4NH₃?

• Subscript

• Superscript

• Coefficient

Multiple Choice

How many Nitrogen (N) atoms are in 4NH₃?

• 4

• 1

• 3

• 12

Multiple Choice

How many Hydrogen (H) atoms are in 4NH₃?

• 4

• 1

• 3

• 12

Multiple Choice

How many total molecules is 4NH₃?

• 4

• 1

• 3

• 12

Multiple Choice

How many total atoms make up 4NH₃?

• 4

• 16

• 3

• 12

Multiple Choice

In the equation shown, what are the product(s)?

• N₂ + H₂

• NH₃

Multiple Choice

To balance an equation you should:

• ONLY change subscripts.

• ONLY change coefficients.

• Change BOTH subscripts and coefficients.

Multiple Choice

What is the left part of a chemical equation called?

2H₂ + O₂ ---> 2H₂O

• Reactants

• Yields

• Products

• Chemical equation

Multiple Choice

What is the right part of a chemical equation called?

2H₂ + O₂ ---> 2H₂O

• Reactants

• Yields

• Products

• Chemical Equation

Multiple Choice

Complete the sentence.

During a chemical reaction, atoms ________.

• can appear

• can disappear

• get rearranged

• stop moving and vibrating

Multiple Choice

What is the Law of Conservation of Mass?

• It states that matter cannot be created or destroyed.

• It states that energy cannot be created or destroyed.

• It states that matter can be created or destroyed.

• It states that sound can be created or destroyed.

Multiple Choice

Balance the following equation:

___ H₂+ ___ O₂→___ H₂O

• 1, 1, 3

• 2, 2, 2

• 1, 2, 1

• 2,1, 2

Multiple Choice

What type of reaction is the equation C + O₂ → CO₂?

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Multiple Choice

What type of reaction is the equation

2NaCl → 2Na + Cl₂?

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Multiple Choice

What type of reaction is the equation

MgCl₂ + Li₂CO₃ → MgCO₃ + 2 LiCl

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Multiple Choice

What type of reaction is the equation

3Pb + 2H₃PO₄ → 3H₂ + 1Pb₃(PO₄)₂

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Multiple Choice

What type of reaction is the equation

Pb + FeSO₄ → PbSO₄ + Fe

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Multiple Choice

What type of reaction is the equation

CaCO₃ → CaO + CO₂

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Multiple Choice

What type of reaction is the equation

P₄ + 3 O₂ → 2 P₂O₃

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement