Lesson 8: Chemical Change

Question 1

Reactant

Answer 1

• Substance that reacts in a chemical reaction

Question 2

Product

Answer 2

• Substance that is produced in a chemical reaction

Question 3

How can you predict elements states in chemical formulas?

Answer 3

• All metals are solid expect mercury
• Most diatomic elements are solid except for bromine (l) and iodine (s)
• Sulfur, phosphorus, and carbon are solid

Question 4

How can you predict compound states in chemical formulas?

Answer 4

• All ionic compounds are solid at room temp
• Molecular compounds are more likely to be gas if their small, liquid if their in the middle and solid of their large

Question 5

Exothermic Reactions

Answer 5

• Energy is released usually in the form of heat, light, or electricity

Question 6

Endothermic Reactions

Answer 6

• Energy is absorbed
• Cold

Question 7

Characteristics in Chemical Reactions

Answer 7

• Creates a new substance
• Changes of state can sometimes be observed
• Involve the flow of energy

Question 8

Law of Conservation of Mass

Answer 8

• The total amount of atoms present before a reaction is equal to the total amount of atoms present after a reaction
• Matter cannot be created or destroyed

Question 9

Precipitate

Answer 9

• Solid that’s formed when two solutions react