2) Lesson - Intro to Chemical Reactions

Question 1

TRUE OR FALSE:

Change in colour
Energy is released or absorbed
A gas is produced
A precipitate forms

Are all hundred precent examples of chemical change

Answer 1

FALSE

Any one of the following clues MAY indicate that a chemical change has produced one

• To be a hundred precent sure is to test the product to show that it is a new substance!

Question 2

Law of Conservation of Mass

Answer 2

the total mass of reactants equals the total mass of products

Question 3

Chemical Reactions can be described by:

Answer 3

Words
Word Equation
Unbalanced or skeleton Equation
Balanced Equation

Question 4

What do state symbols tell us?

Answer 4

the state, or form, of each substance in a chemical equation

Question 5

aq

Answer 5

dissolved in water