Balancing Chemical Equations

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.

Tags

NGSS.MS-PS1-5

What is the part of the chemical equation in green called? Fe + S --> FeS

• products

• reactants

• yield

• chemical formula

What coefficient should be used to make the following equation balanced?

N₂+O₂--> __?__NO

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

Is the following equation balanced?
4Fe + 3O₂ --> 2Fe₂O₃

• yes

• no

Tags

NGSS.MS-PS1-5

What does the Law of Conservation of Mass say? It says, "During a chemical reaction, mass is neither _______ or destroyed."

• burned

• created

• melted

Tags

NGSS.MS-PS1-5

So, the Law of Conservation of Mass would tell us that the mass of all the REACTANTS must __________ the mass of all PRODUCTS in a chemical reaction.

• equal

• be greater than

• be less than

Tags

NGSS.MS-PS1-5

According to the Law of Conservation of Mass (Matter), Matter cannot be ​ (a)   or ​ (b)   , it can only be ​ (c)   . This means however many atoms of an element we have before a reaction must be ​ (d)   to the number after a reaction.

• created

• destroyed

• changed

• equal

Tags

NGSS.MS-PS1-5

What is the number before a chemical formula called?
Ex: 2H₂ + O₂ --> 2H₂O

• Coefficient

• Subscript

• Atom

• Equation

What is the primary goal when balancing a chemical equation?

• To ensure the equation is aesthetically pleasing

• To make sure the number of atoms for each element is equal on both sides

• To increase the number of products

• To reduce the number of reactants

Tags

NGSS.MS-PS1-5

Which of the following is a balanced chemical equation?

• @@ ext{C}_3 ext{H}_8 + 5 ext{O}_2 ightarrow 3 ext{CO}_2 + 4 ext{H}_2 ext{O}@@

• @@ ext{C}_3 ext{H}_8 + 4 ext{O}_2 ightarrow 3 ext{CO}_2 + 4 ext{H}_2 ext{O}@@

• @@ ext{C}_3 ext{H}_8 + 6 ext{O}_2 ightarrow 3 ext{CO}_2 + 4 ext{H}_2 ext{O}@@

• @@ ext{C}_3 ext{H}_8 + 3 ext{O}_2 ightarrow 3 ext{CO}_2 + 4 ext{H}_2 ext{O}@@

Tags

NGSS.MS-PS1-5