Chapter C1 Atomic Structure

Question 1

What is an atom?

Answer 1

The smallest part of a chemical element that can exist

Question 2

What is an element?

Answer 2

Substance made of one type of atom

Question 3

What is the law of conservation of mass?

Answer 3

The total mass of the products equals the total mass of the reactants

Question 4

What is a mixture?

Answer 4

A mixture is made up of two or more substances that are not chemically combined together

Question 5

What is a compound?

Answer 5

A substance formed when two or more elements are chemically bonded together

Question 6

What are the state symbols?

Answer 6

S- solids
G-gas
L-liquids
Aq- aqueous solution

Question 7

What are differences between mixtures and compounds?

Answer 7

Compounds have a fixed composition whilst mixtures do not

Compounds require separation by chemical reaction- mixtures do not

Compounds have chemical bonds between atoms- mixtures do not

Question 8

What is the atomic number?

Answer 8

Number of protons in an element?

Question 9

What is an ion?

Answer 9

A charged atom or group of atoms

Question 10

What is an isotope?

Answer 10

Atoms of the same element with a different number of neutrons

Question 11

How do you calculate the mass of neutrons?

Answer 11

The mass number- the atomic number

Question 12

How is an atom negatively charged?

Answer 12

If there are more electrons than protons

Question 13

How is an atom positively charged?

Answer 13

If there are more protons than electrons

Question 14

Describe the basic structure of an atom

Answer 14

Nucleus containing protons and neutrons with electron shells orbiting it

Question 15

Describe the technique of filtration?

Answer 15

If you have one soluble substance and one insoluble, add water so one dissolves into the water. Then put it through filter paper. The insoluble one will then be on the filter paper, whilst yeh soluble one will pass through with the solvent

Question 16

What is filtration used for?

Answer 16

To separate substances that are insoluble in a particular solvent, from substances that are soluble in the solvent

Question 17

What is crystallisation used for?

Answer 17

To separate absolute from a solvent

Question 18

Describe the process of crystalissation

Answer 18

Put the solution over a heat source- the solvent will evaporate leaving the solute behind

Question 19

What is distillation used for?

Answer 19

To separate solvent and a solute without losing the solvent

Question 20

Describe the process of distillation

Answer 20

The solution is placed over a heart source. The solvent evaporated, and rises into a condenser. This has a cooler temperature and so changes the state of the water vapour back into a liquid. This then means you will have a separated solute and solvent

Question 21

What is fractional distillation used for?

Answer 21

This is used to separate two liquids with different boiling points

Question 22

Describe the process of fractional distillation

Answer 22

A solution is heated to a specific boiling point, at which time one of the liquids begins to evaporate. This vapour then rises into a fractioning column, where cool glass beads ensure that if the other liquid has begun to evaporate it condenses. The gas then passed into a condenser and is collected separately

Question 23

What is chromatography used for?

Answer 23

Used to separate and identify substances from mixtures in a solution

Question 24

Describe the process of chromatography

Answer 24

A piece of chromatography paper has a line drawn on it. The solution is then spotted onto the line at separate points, this is then placed in a solvent, and the solvent soaks up the paper, running through the spot of the solution. The relative solubility if the components displays how far up the paper they travel, with the more soluble substances travelling further up the paper

Question 25

Who first came up with the idea of the atom?

Answer 25

Greeks

Question 26

What did John Dalton do?

Answer 26

Suggested substances were made up of atoms Suggested atoms rearranged in reactions Suggested they could not be split

Question 27

What did Geiger and marsden do?

Answer 27

Alpha particle experiment- fired alpha particles at golden foil. They expected them to go straight through- some of the alpha particles rebounded tho- this meant something in the middle was positively charged- the electrons were orbiting around a nucleus which contained dense protons

Question 28

What did J.J Thompson do?

Answer 28

Discovered the electron Found that the beams of particles were attracted to positive charge and so had to be negatively charged. This proved Dalton was wrong and electrons were embedded in an atom. He suggested the plum pudding model

Question 29

What did Bohr suggest?

Answer 29

Found that the light given out when atoms were heated had specific energy amounts- suggested electrons orbited in shells

Question 30

What did James Chadwick do?

Answer 30

Neutrons were discovered as the nucleus had a missing mass- James Chadwick did an experiment only explainable by neutrons

Question 31

What are the charges of a proton, neutron and electron?

Answer 31

-1 0 1

Question 32

What is the mass number?

Answer 32

The number of protons+ neutrons

Question 33

What is electronic strutcture?

Answer 33

A set of numbers to show the arrangement of electrons in their shells

Question 34

What is the maximum amount of electrons in the first, second and third shell?

Answer 34

2 8 8