Science Chemical Change

Question 1

Physical change

Answer 1

type of change where the physical properties of matter change.
- No new product
-easily reversible
-Atoms are not rearranged

Question 2

Chemical change

Answer 2

a change of materials into another, new materials with different properties and one or more than one new substances are formed.
-new product formed
-atoms are rearranged

Question 3

Reactants

Answer 3

the substance present at the start of a chemical reaction.

Question 4

Products

Answer 4

the substances formed by chemical reactions

A+B->AB

Question 5

For a chemical reaction to occur the …. between ….. must be ……

Answer 5

For a chemical reaction to occur the bonds between atoms must be broken.
AB+C->A+BC

Question 6

Names for Formulas

Answer 6

most formulas are based directly on the name of the substance. The ending of the last element has been changed to ide.
Magnesium +Flourine
MgF-> Magnesium Flouride

Question 7

mono

Answer 7

1

Question 8

di

Answer 8

2

Question 9

tri

Answer 9

3

Question 10

treta

Answer 10

4

Question 11

penta

Answer 11

5

Question 12

hexa

Answer 12

6

Question 13

hydrogen

Answer 13

H+

Question 14

lithium

Answer 14

Li+

Question 15

sodium

Answer 15

NA+

Question 16

potassium

Answer 16

K+

Question 17

silver

Answer 17

Ag2+

Question 18

magnesium

Answer 18

Mg2+

Question 19

Calcium

Answer 19

Ca2+

Question 20

Barium

Answer 20

Ba2+

Question 21

Zinc

Answer 21

Zn2+

Question 22

Aluminum

Answer 22

Al3+

Question 23

Fluoride

Answer 23

F-

Question 24

chloride

Answer 24

Cl-

Question 25

bromide

Answer 25

Br-

Question 26

iodide

Answer 26

I-

Question 27

oxide

Answer 27

O2-

Question 28

sulfide

Answer 28

S2-

Question 29

ammonium

Answer 29

NH4+

Question 30

Hydroxide

Answer 30

OH-

Question 31

Carbonate

Answer 31

CO3 2-

Question 32

nitrate

Answer 32

NO3

Question 33

Phosphate

Answer 33

PO4 3-

Question 34

Sulfate

Answer 34

SO4 2-

Question 35

hexa

Answer 35

6

Question 36

Solid

Answer 36

(S) (frozen,hard, powder,turnings)

Question 37

Liquid

Answer 37

(L)

Question 38

Gas

Answer 38

(G) steam, bubble, fizz

Question 39

Aqueous

Answer 39

(Aq) something dissolved in water) (Solution, Aqueos, dissolved)

Question 40

Ionic formula

Answer 40

drop it and swap it

Question 41

The law of conservation of mass

Answer 41

The law of conservation of mass states that matter can neither be created or destroyed in a chemical reaction but transferred or transformed.

Question 42

The law of conservation of mass Atoms

Answer 42

During a chemical change there is no loss or gain of atoms.

Question 43

The law of conservation of mass Equation

Answer 43

In an equation you must have even amounts of elements on both sides.

Question 44

Exothermic

Answer 44

In an exothermic reaction heat light or electricity is released into the surroundings. When heat is released the surroundings become hot. Eg. A fire giving of heat, freezing ice, water and calcium chloride

Question 45

Endothermic

Answer 45

In an endothermic reaction heat is absorbed from the surroundings and they become cold. eg. snowman melting, melting, boiling

Question 46

Combustion

Answer 46

metals react with oxygen

Question 47

Combustion formula

Answer 47

Fuel + Oxygen -> carbon dioxide + water

Question 48

Combustion reaction rates

Answer 48

Some combustion reactions happen very fast eg an explosion. Combustion can happen at different rates. An example of a slow reaction is putting gas in a gas bottle and using it to cook something while camping.

Question 49

All metals react apart from.....

Answer 49

Gold and silver

Question 50

Acids

Answer 50

substances taste sour and can burn. All aciids have similar chemical properties. acids react with most metals.

Question 51

Base

Answer 51

taste bitter and feel soapy.

Question 52

alkaline

Answer 52

bases that dissolve in water

Question 53

indicators

Answer 53

Indicators are substances that have a different colour in an acid or a base. Universal indicator is a mixture of many indicators. It is used to indicate the strength of the acid or base.

Question 54

Ph

Answer 54

The pH scale lets us see the relative acidity or alkalinity of a solution The stronger the acid the lower the pH The stronger the base the higher the pH