Chemical Reactions

Question 0

Elements-

Answer 0

Can not be broken down, simplest type of substance

Question 1

Chemistry-

Answer 1

Study of properties of matter and how matter changes

Question 2

Compound-

Answer 2

two or more elements chemically combined

Question 3

Mixture-

Answer 3

two or more pure substance mixed but NOT chemically combined

Question 4

Solution-

Answer 4

Well mixed mixture

Question 5

Physical change-

Answer 5

breaks into smaller pieces but still the same material

EX: Ice

Question 6

Chemical Change-

Answer 6

a change in matter that makes new substances

Question 7

Precipitate-

Answer 7

a solid that forms from a solution

Question 8

Relative humidity-

Answer 8

the moisture in the air

Question 9

Atoms-

Answer 9

smallest particle of an element

Question 10

Molecule-

Answer 10

smallest part of a compound

Question 11

Chemical bonding-

Answer 11

force that holds chemicals together

Question 12

All the matter around you is composed of______________

Answer 12

one element or a combination of two or more elements

Question 13

What are some types of solutions/mixtures?

Answer 13

Salt water, soil, sand, clay,

Question 14

A chemical bond is formed or broken down during a ________

Answer 14

chemical reaction

Question 15

What are 5 evidences of a chemical reaction?

Answer 15

Color change, Precipitation, Gas Production, Changes in Temperature, Changes in properties

Question 16

Chemical formula

Answer 16

shows a ratio of elements in a compound

Question 17

Subscript-

Answer 17

shows the number of atoms of an element, written below the letter

Question 18

Coefficient-

Answer 18

number in front of a formula; shows the number of molecules in the formula

Question 19

Reactant-

Answer 19

found on the left side of the arrow or yield sign

Question 20

Product-

Answer 20

found on the right side of the arrow or yield sign

Question 21

Chemical equation-

Answer 21

a shorter and easier way to show chemical reactions

Question 22

a chemical reaction uses symbols to show__________

Answer 22

the reactants and products

Question 23

Conservation of mass-

Answer 23

the amount of matter in a chemical reaction never changes, so the total mass of the reactants must equal the total mass of the product

Question 24

Synthesis-

Answer 24

Mg+ CO= 2MgCo

adding to make one unit

Question 25

Decomposition-

Answer 25

2MgCO= Mg+ CO

One unit being broken down

Question 26

Replacement-

Answer 26

Mg+ CO= 2CO+ 3Mg

Question 27

What are the ways to speed up a Chemical reaction?

Answer 27

1. To increase the surface area,
2. To increase temperature
3. To increase concentration

Question 28

Exothermic reaction-

Answer 28

A reaction the releases energy in the form of heat

Question 29

Endothermic reaction-

Answer 29

A reaction that absorbs energy

Question 30

Activation energy

Answer 30

the minimum amount of energy that is added to start a reaction

Question 31

Concentration-

Answer 31

the amount of one material in a given volume of another material

Question 32

Catalyst

Answer 32

the material that increases the rate of a reaction by lowering the activation energy

Question 33

enzymes-

Answer 33

the cells that contain catalysts

Question 34

inhibitor-

Answer 34

a material used to decrease the rate of a reaction