Final study (chapter2)

Question 1

What are the changes in matter

Answer 1

Physical Change - any change that alters the form or appearance of the substance but that does not make the substance into another substance
Examples: squash a marshmallow, braiding your hair, origami
Chemical reaction - change in matter that produces one or more substances

Question 2

Where are the reactants and products of a chemical reaction located?

Answer 2

Reactants are before the “yield” sign and the products are after the “yield”

Question 3

What is the principle of conservation of mass? What is an example?

Answer 3

Conservation of Mass: During a chemical reaction matter is created or destroyed
Example: Burning wood: the total mass of the wood and oxygen used in the burning = the mass of the ash and gases

Question 4

What is the difference between an open and closed system?

Answer 4

Open System: matter can enter from or escape to its surroundings
Closed System: matter is not allowed to enter or leave

Question 5

Can you identify it as synthesis, decomposition, single replacement, or double replacement?

Answer 5

Synthesis - when two elements form into one substance
A + B → AB
Decomposition - when a substance forms into two elements
AB → A + B
Single Replacement - one element replaces another element in a compound
A + BC → AC + B
Double Replacement - Two elements replace each other in different compound
AB + CD → AD + CB