Balancing Chemical Equations

Balancing Chemical Equations

Lesson about the parts of a chemical equation and how to balance chemical equations.

Multiple Choice

What does a chemical change result in?

• A change in state of the substance (ex. liquid to solid)

• A change in texture of the substance.

• A change in the way atoms are bonded to each other.

• A change in the appearance of the substance.

Multiple Choice

The difference between a Physical change and a Chemical change is…

• Physical change is only a change to the outside appearance.

• Chemical change is when matter is changed into something new.

• Atoms are rearranged in chemical changes & not in physical.

• All are correct.

Multiple Choice

Which of the following could indicate that a chemical change took place?

• Change in color

• Production of Energy

• Formation of Gas

• All are correct

Multiple Choice

Identify the reactant(s) and product(s) of the reaction.

• All three are reactants and none are products.

• Hydrogen and water are the reactants, and oxygen is the product.

• Water and oxygen are the reactants, and hydrogen is the product.

• Hydrogen and oxygen are the reactants, and water is the product.

Multiple Choice

The substances listed on the left side of a chemical equation are the

• Products

• Coefficients

• Precipitates

• Reactants

Multiple Choice

The substances listed on the right side of a chemical equation are the

• Yields

• Reactants

• Products

• Precipitates

Multiple Choice

In chemical reactions, what does the principle of conservation of mass mean?

• Matter is not created or destroyed.

• The total mass of the reactants is greater than the total mass of the products.

• The total mass of the reactants is less than the total mass of the products.

• Matter is not changed.

Multiple Choice

Diatomic molecules are __________ found in nature as their single element: I, O, N, H, Br, Cl, or H.

• often

• never

• sometimes

• always

Multiple Choice

N_2, Cl_{2, and} O₂ are all

• diatomic molecules.

• ionic bonds.

• of equal mass.

• solids.

2 H₂ + 1 O₂ --> 2 H₂O

Multiple Choice

What are the larger numbers that you CAN CHANGE in a chemical equation?

• Coefficient

• Products

• Reactants

• Subscripts

Multiple Choice

What are the smaller numbers that you CANNOT change in a chemical equation?

• Coefficient

• Products

• Reactants

• Subscript

Multiple Choice

How many aluminum atoms are in Al₂(SO₄)₃?

• 1

• 2

• 3

• 4

Multiple Choice

What is the number before a chemical formula called?

Ex: 2H₂ + O₂ --> 2H₂O

• Coefficient

• Subscript

• Atom

• Equation

Multiple Choice

What is the little number after an element in a chemical equation called.

Example: H₂

• Coefficient

• Subscript

• Atom

• Equation

Multiple Choice

How many atoms of carbon (C) are in C₆H₁₂O₆?

• 3

• 6

• 12

• 24

Multiple Choice

Which number should go in the blank?
2 Na+ _ Cl₂ -> 2 NaCl

• 1
• 2
• 3
• 0

Multiple Choice

Balance this equation

_Al +_HCl --> _H₂ +_AlCl₃

• 2, 6, 3, 2

• it is already balanced

• 4, 12, 3, 4

• 2, 1, 4, 5

Multiple Choice

Balance this equation.

_CF₄ + _Br₂ --> _CBr₄ + _F₂

• 2,1,2,1

• 1,2,2,1

• 1,2,1,2

• 2,2,2,2

Multiple Choice

How many HCl molecules do you need to balance this equation?

Mg + __HCl ---> MgCl₂ + H₂

• 1

• 2

• 3

• 4

Multiple Choice

Which of the following shows the correct way to balance the chemical equation?

Fe + O₂ -> Fe₂O₃

• 4Fe + 3O₂ -> 2Fe₂O₃

• 2 Fe + 3O₂ -> Fe₂O₆

• 4 Fe + O₆ -> 2Fe₂O₃

• None of the options are correctly balanced.

Multiple Choice

Which of the following reactions is balanced?

• 2CH₄ + O₂ -> CO₂ + H₂O

• CH₄ + 2O₂ -> CO₂ + H₂O

• CH₄ + 2O₂ -> CO₂ + 2H₂O

• None of the chemical equations are balanced.

Multiple Choice

Balance this equation.

_CH₄ + _O₂ --> _CO₂ + _H₂O

• 1,2,1,1

• 2,1,2,1

• 1,2,1,2

• 0,2,0,2