Signs of a Reaction, Balancing a Reaction, Types of Reactions

The elements / compounds on the LEFT side of the yield arrow are known as

• Products

• Metals

• Reactants

• Chemicals

Answer explanation

The elements/compounds on the LEFT side of the yield arrow are known as Reactants.

Tags

NGSS.HS-PS1-7

The elements / compounds on the RIGHT side of the yield arrow are known as

• Reactants

• Gases

• Chemicals

• Products

Answer explanation

The elements/compounds on the RIGHT side of the yield arrow are known as Products.

Tags

NGSS.MS-PS1-5

What are the reactants of this equation?

Answer explanation

The correct reactants of the equation are N2 and H2, as indicated by the formula N2 + H2.

Answer explanation

The correct products of the equation are Al₂(SO₄)₃, as indicated by the balanced chemical equation.

The number of atoms you begin with in a chemical reaction ...

• must be the same as the number of  atoms you end with

• must be an even number

• can be different to the number you finish with

• changes depending on how much energy is formed

Answer explanation

The number of atoms you begin with in a chemical reaction must be the same as the number of atoms you end with.

Tags

NGSS.MS-PS1-5

What mathematical function do coefficients perform in a balanced equation?

• addition

• subtraction

• multiplication

• division

Answer explanation

Coefficients perform multiplication in a balanced equation to determine the number of each molecule involved in the reaction.

Which set of coefficients correctly balances the following:

____ Al + ____ O₂ → ____ Al₂O₃

• 2,3,4

• 4,3,2

• 1,1,2

• 2,1,1

Answer explanation

The correct coefficients to balance the equation are 4, 3, 2. This ensures that the number of atoms on both sides of the equation is equal.

Tags

NGSS.HS-PS1-7

Which type of reaction is: C₂H₄ + 3 O₂ → 2 CO₂ + 2 H₂O

• Synthesis

• Decomposition

• Single Replacement

• Combustion

Answer explanation

The given reaction involves the burning of C2H4 in the presence of oxygen to produce CO2 and H2O, which is characteristic of a combustion reaction.

Which type of reaction is:

2 NaBr + Ca(OH)₂ → CaBr₂ + 2 NaOH

• Synthesis

• Single Replacement

• Double Replacement

• Combustion

Answer explanation

The given reaction is a Double Replacement reaction where the cations and anions of two compounds switch places to form two new compounds.

Which type of reaction is:

2 NH₃ + H₂SO₄ → (NH₄)₂SO₄

• Synthesis

• Decomposition

• Single Replacement

• Double Replacement

Answer explanation

The given reaction is a Synthesis reaction where two reactants combine to form a single product.