Atomic Structure

Question 1

Define an Element

Answer 1

A substance made up of only one type of atom.

Question 2

How many blocks are there in the periodic table of elements?

Answer 2

There are 4 main blocks: S-block, D-block, P-block and F-block.

Question 3

How many Groups are there in the periodic table?

Answer 3

8 groups.

Question 4

Which group contains the alkali metals?

Answer 4

Group 1

Question 5

Which Group contains the noble gases?

Answer 5

Group 0 (also called 8)

Question 6

Which Group contains the alkali earth metals?

Answer 6

Group 2

Question 7

Which Group contains the halogens?

Answer 7

Group 7.

Question 8

Where are the transition metals?

Answer 8

In the middle! Between Groups 2 and 3.

Question 9

Where are the non-metals?

Answer 9

Between groups 3-6. The elements that are part of non-metals that make the boarder to the transition metals are: B,Si,As,Te
Remember (Bee-see-ay-tee)

Question 10

Which elements are in the separate bars from the rest of the periodic table?

Answer 10

Lanthanides and Actinides

Question 11

What is a molecule?

Answer 11

A grouping of two or more atoms bonded together. The bonds are hydrogen bonds.

Question 12

Describe the structure of an atom

Answer 12

An atom has a nucleus made of protons and neutrons. Protons have a positive charge, neutrons do not have a charge. The nucleus is surrounded by electrons, a tiny particle with a negative charge.

Question 13

What is a reactant?

Answer 13

A substance you start with that you are going to use in a chemical reaction.

Question 14

What is a product?

Answer 14

The substance that is made in a chemical reaction.

Question 15

What happens to atoms in a chemical reaction?

Answer 15

The atoms are rearranged.

Question 16

What do we mean by a balanced equation?

Answer 16

There are the same number of each type of atom on both sides of the equation. This means that the mass of the products is the same as the mass of the reactants.

Question 17

What is the Law of conservation of mass?

Answer 17

The total mass of the products is equal to the total mass of the reactants.

Question 18

What are state symbols?

Answer 18

When you write an (S) (L) (G) or (Aq) next to the compound’s name to tell you if it is a solid, liquid, gas or dissolved in water.

Question 19

What is a mixture?

Answer 19

A mixture is a combination of two or more substances (elements or compounds) that are not chemically combined together.

Question 20

What are the 3 main differences of compounds vs mixtures?

Answer 20

Compounds have a fixed composition in proportions, mixtures do not. Compounds always need chemical reactions to separate their elements, mixtures do not (sometimes can just physically mix it). And finally, there are chemical bonds between atoms of different elements in a compound- there are not bonds between different substances (elements or compounds) in a mixture.

Question 21

Which methods can separate substances in a mixture?

Answer 21

Filtration, crystallisation, distillation, chromatography.

Question 22

When is filtration used?

Answer 22

When separating an insoluble substance from a soluble substance. This occurs in a solvent - a dissolving material.

Question 23

when is Crystallisation used?

Answer 23

When trying to obtain a crystal or salt in isolation.

Question 24

When is Distillation used?

Answer 24

When you want to collect and separate all solids and liquids.

Question 25

When is fractional distillation used?

Answer 25

When separating mixtures of miscible liquids, that each have different boiling points.

Question 26

What are the steps of fractional distillation?

Answer 26

1- Boil substance so it evaporates
2- Vapours pass over glass beads
3- Higher boiling point gases will cool lower in the bead column and drip back in the flask as liquid
4- Lower boiling point gases will rise higher and pass into a condenser, collecting here as liquid

Question 27

In which situation is fractional distillation commonly used?

Answer 27

To separate ethanol as biofuel.

Question 28

What happens in paper chromatography?

Answer 28

Substances dissolved in a solvent move up the chromatography paper.
The substances have different solubilities, so separate at different lengths of the paper.

Question 29

What is a chromatogram?

Answer 29

The record of the separation results from paper chromatography.

Question 30

What was the atom in Thomson’s Plum Pudding model?

Answer 30

Electrons in a cloud of positive charge

Question 31

In evidence for the nucleus, what did Geiger and Marsden propose?

Answer 31

That electrons are orbiting the nucleus and the nucleus must contain positive protons.

Question 32

In evidence for electrons who suggested electrons have energy levels?

Answer 32

Bohr said electrons are ‘excited’ (because they have negative charge) and are so shot out at different distances (energy levels) from the nucleus. When they fall levels, energy is released.

Question 33

Who discovered the neutron?

Answer 33

Chadwick