Atoms elements compounds and mixtures

Question 1

Whats a compound

Answer 1

A substance containg two or more elements, which are chemically bonded

Question 2

How can you separate compounds?

Answer 2

By chemical reactions or electroylsis

Question 3

Which side of the equation are the reactants on?

Answer 3

The left hand side

Question 4

What side of the equation are the products on?

Answer 4

The right hand side

Question 5

What’s a mixture?

Answer 5

Two or more elements or compounds that aren’t chemically bonded

Question 6

The components in a mixture still maintain their properties. True or False

Answer 6

True

Question 7

What processes can be used to separate mixture?

Answer 7

Physical processes
.No chemical reactions are neccesary

Question 8

What’s filtration used for?

Answer 8

Used to separate insoluble solids from soluble solids
Eg: sand and salt in water

Question 9

What’s crystallisation used for?

Answer 9

Used to obtain soluble solids from a solution
Eg: salt from salt water

Question 10

What’s simple distillation used for?

Answer 10

Used to obtain a solvent from a solution

Question 11

What’s fractional distillation used for?

Answer 11

Used to separate mixtures in which the components have different boiling points

Question 12

What’s chromatography used for?

Answer 12

Used to separate the different soluable, coloured components of a mixture
Eg: separating coloured dyes in a sloution

Question 13

What was the earliest model of an atom thought to be?

Answer 13

Tiny spheres that couldn’t be divided into smaller particles

Question 14

What was the name of the man that discovered electrons?

Answer 14

Thomson

Question 15

What year were electrons discovered?

Answer 15

1898

Question 16

What did Thomson discover?

Answer 16

Electrons

Question 17

What is the overall charge of an atom

Answer 17

0
. Neutral

Question 18

What’s the overall charge of an electron?

Answer 18

-1
.Negative

Question 19

What’s the plum pudding model?

Answer 19

A ‘pudding’ of positive charge with ‘raisins’ of negative electrons dotted around

Question 20

What experiment did Geiger and Marsden conduct?

Answer 20

They fired alpha particles at a thin sheet of gold

Question 21

What happened in the Geiger and Marsden experiment? (gold foil)

Answer 21

Most of the positively charged alpha particles passed right through the atoms, but a small number were deflected back towards the souce

Question 22

Who discovered the nucleus?

Answer 22

Rutherford

Question 23

What did Rutherford determine?

Answer 23

That the positive charge in an atom must be concentrated in a small area

Question 24

What model replaced the plum pudding?

Answer 24

The nuclear model

Question 25

Who discovered that electrons orbit the nucleus in shells?

Answer 25

Bohr

Question 26

Who proved the evidence of neutrons within the nucleus?

Answer 26

James Chadwick

Question 27

Relative mass of a proton

Answer 27

1

Question 28

Relative mass of a neutron

Answer 28

1

Question 29

What does the atomic number of an element represent?

Answer 29

The number of protons in it

Question 30

What's the equation for the number of neutrons?

Answer 30

Mass number-atomic numer

Question 31

What's an isotope?

Answer 31

An element that has the same number of protons but a different number of neutrons

Question 32

What happens to atoms when they loose or gain electrons?

Answer 32

They become an ion

Question 33

How many electrons can the first shell hold in the first 20 elements?

Answer 33

Maximum 2

Question 34

How many electrons can the second shell hold in the first 20 elements?

Answer 34

Maximum 8

Question 35

Who created the modern periodic table?

Answer 35

Mendeleev

Question 36

When did mendeleev create his periodic table?

Answer 36

1869

Question 37

What elements are in group 0

Answer 37

Noble gases

Question 38

Why are noble gases unreactive?

Answer 38

As they have a full outer shell

Question 39

What elements are in group 1?

Answer 39

The alkali metals

Question 40

How many electrons in an alkali metals outer shell?

Answer 40

1

Question 41

Do alkali metals have high or low melting and boiling points?

Answer 41

Low that decrease down the group They get more reactive further down the group

Question 42

Why do alkali metals get more reactive further down the group?

Answer 42

As the outer electrons gets further away, meaning it's easier to loose

Question 43

What are alkali metals stored in and why?

Answer 43

Oil, as they can easily react with water and the air

Question 44

What are the products when an alkali metal reacts with water?

Answer 44

Metal hydroxide Hydrogen gas

Question 45

Do group 1 metals have a high or low density?

Answer 45

Low density

Question 46

What happens when alkali metals react with non metals?

Answer 46

They form ionic compounds When this happens the metal ion loses one electron to form a metal ion with a positive charge