Atomic Structure and the Periodic Table GCSE

Question 1

Atom

Answer 1

Smallest part of an element that can exist

Question 2

Compounds

Answer 2

Contain two or more elements chemically combined

Question 3

Mixture

Answer 3

Contains two or more elements that are not chemically combined

Question 4

Plum pudding model

Answer 4

• Suggested atom is a ball of positive charge

- With electrons embedded in it

Question 5

What was the alpha particle experiment?

Answer 5

• Rutherford
• Nuclear model
• Fired alpha particles at a sheet of thin gold
• Most went through
• Some were repelled and redirected
• Some bounced directly off
• Concluded that the mass of an atom was concentrated at the center and that the nucleus was charged

Question 6

What did Neil’s Bohr develop?

Answer 6

• Suggested that the electrons orbited the nucleus
• At specific distances
• Called shells

Question 7

What did James Chadwick propose?

Answer 7

• Proved existence of neutrons within nucleus

Question 8

Size of atoms

Answer 8

Radius of -

• 10^-10 m

Question 9

What are isotopes?

Answer 9

Atoms of the same element with different numbers of neutrons

Question 10

Groups

Answer 10

Vertical columns of elements

Question 11

How were periodic tables arranged in their early discovery?

Answer 11

In order of their atomic weights

Some elements were placed in the wrong group

Question 12

What did Mendeleev develop?

Answer 12

• Left gaps in the periodic table for elements which he thought had not been discovered yet

Question 13

What ions do metals form?

Answer 13

Positive

Question 14

What ions do non-metals form?

Answer 14

Negative

Question 15

Group 0

Answer 15

• Noble gases
• Unreactive (full outer shells)
• Boiling point increases as it goes down the group

Question 16

Group 1

Answer 16

• Alkali metals
• Reactivity of metals increase down the group
• Very reactive (1 outer electron)
• boiling point and melting point decrease down the group

Question 17

Reactions of group 1 metals with OXYGEN

Answer 17

React with oxygen in the air

Question 18

Reactions of group 1 metals with WATER

Answer 18

React with water to produce a metal hydroxide + hydrogen

Sodium hydroxide is an alkali, which is a base which will dissolve in water to form an alkaline solution.

Hydrogen gas produced, and in reactive metals such as potassium, hydrogen burns as the reaction takes place

Question 19

Reactions of group 1 metals with GROUP 7 ELEMENTS

Answer 19

Forms a normal reaction, eg. Lithium + Chlorine = Lithium Chloride

Question 20

Group 7

Answer 20

• Halogens
• Diatomic non-metals
• Less reactive as you go down the group
• Boiling point increases down the group
• A more reactive halogen can displace a less reactive halogen from an AQUEOUS solution of its salt

Question 21

Transition metals

Answer 21

• Useful catalysts
• Ions with different charges
• Good conductors
• Malleable
• High densities
• High melting points
• Low reactivity