Materials

Question 1

What did Thomson do?

Answer 1

Develop the plum pudding model-positively charged atoms with electrons embedded in them. 1903

Question 2

What did Bohr do?

Answer 2

Create the shell model-atoms consisting of a positive nucleus with electrons in certain orbits or fixed energy called shells. 1913

Question 3

What did Rutherford do?

Answer 3

Create the solar system model-the atom was a mostly empty space with a positively charged nucleus and electrons orbiting the nucleus. 1911

Question 4

What did Chadwick do?

Answer 4

He added neutrons to the shell model, this is the model we use. 1932

Question 5

How many electrons fit in the first three shells of an atom?

Answer 5

2,8,8

Question 6

What is an electron?

Answer 6

A negative subatomic particle that orbits the nucleus in fixed shells of energy

Question 7

What is the nucleus of an atom made up of?

Answer 7

Neutrons(neutral) and protons(positive)

Question 8

What is the mass of a proton/neutron?

Answer 8

1

Question 9

What is the mass of an electron?

Answer 9

0

Question 10

What is the top number on an atom on a periodic table?(atomic number)

Answer 10

The amount of protons and neutrons

Question 11

How do you find the amount of neutrons?

Answer 11

Atomic mass minus atomic number

Question 12

What are electrons in the outmost shell called?

Answer 12

Valence electrons

Question 13

What are 4 properties of metals?

Answer 13

Good conductors of electricity, good conductors of heat, malleable and ductile

Question 14

What are pure metals?

Answer 14

Metals found as jut itself in nature-not in an alloy or ore

Question 15

What are alloys?

Answer 15

Two metals mixed together

Question 16

What is a base metal?

Answer 16

A metal that goes into an alloy

Question 17

Two examples of alloys

Answer 17

Brass and bronze

Question 18

What is the advantage of an alloy over it’s base metal?

Answer 18

It has the properties of both metals

Question 19

What are uses and properties of brass?

Answer 19

Uses-it can be used for decoration, plumbing and electrical, things requiring low friction like doorknobs, locks, and musical instruments.
Properties- low friction, highly workable and durable

Question 20

What are the properties and uses of bronze?

Answer 20

Uses- coins, springs, turbines and blades

Properties- good conductors and low friction

Question 21

What does an acid give off when put in water?

Answer 21

An H+ ion

Question 22

What does an alkali/base give off in water?

Answer 22

An (OH)- ion

Question 23

What is an ion?

Answer 23

A charged atom

Question 24

What are the properties of acids?

Answer 24

Can be corrosive, sour to taste, found in sour foods, eg. Vinegar and less than 7 on the pH scale

Question 25

What are the properties of alkalis/bases

Answer 25

Can be caustic, bitter to taste, used in cleaning products and have a pH more than 7

Question 26

What is pH?

Answer 26

A measure of acidity and alkalinity where each number is ten times bigger than the last

Question 27

What is the neutralisation reaction?

Answer 27

Acid+base----->salt+water | Eg. HCl+NaOH----->NaCl+H2O

Question 28

Why do we need to develop new materials?

Answer 28

Most plastics are made from oil, a finite source

Question 29

How have plastics improved?

Answer 29

Rather than thermo setting plastic which can't melt once its set, we have thermal plastics with can be melted and therefore recycled etc. they are also cheaper

Question 30

What did Democritus do?

Answer 30

He made the indivisible particle model. 350BC

Question 31

Element

Answer 31

Pure substance made up of one type of atom

Question 32

Compound

Answer 32

Pure substance made up of two or more atoms chemically combined in fixed ratios