C1 Atomic Structure

Question 1

What are all substances made out of?

Answer 1

Atoms and there around 100 of them

Question 2

What is the name for substances made out of only one atom?

Answer 2

Elements

Question 3

Where are all the elements and their symbols shown?

Answer 3

In the periodic table

Question 4

What do the symbols represent?

Answer 4

The element/atom name

Question 5

Where are the metals found on the table?

Answer 5

to the left side of the table where there is a staircase going from group 3-7

Question 6

Where are non metals found?

Answer 6

On the right side

Question 7

What are the elements in the table arranged into?

Answer 7

columns called periods

Question 8

What are compounds?

Answer 8

Different types of atoms/elements bonded together

Question 9

What are atoms made out of?

Answer 9

Nucleus containing protons and neutrons and electrons orbiting in shells on the edge of the atom.

Question 10

What do chemical reactions show?

Answer 10

The reactants (the substances you start out with) and the product (the substance you end with)

Question 11

What do symbol equations do that word equations don’t?

Answer 11

Let you see how much each element is involved.

Question 12

What does it mean when the reaction is balanced?

Answer 12

There are the same amount of elements on both sides of the reaction

Question 13

What is the Law of conservation of mass?

Answer 13

The total mass of the products formed in the reaction is equal to the total mass of the reactants.(mass cant be created or destroyed)

Question 14

Why when Calcium Carbonate is heated it appears to lose mass even though the products are the same mass as the reactants.

Answer 14

When the reactant is heated carbon dioxide is given off and then the products look smaller as mass is loss when co2 is released.

Question 15

What are the 4 state symbols to put next to the symbol name of the equations.

Answer 15

solid (s),liquid(l), gas(g),aqueous(aq) which means dissolved in water

Question 16

What is a mixture?

Answer 16

2 or more elements not chemically bonded together

Question 17

Differences between mixtures and compound

Answer 17

compounds have a fixed amount of atoms and have to be seperated using chemical reactions and are chemically bonded while mixtures dont have a fixed amount can be separated physically and have no chemical bonds.

Question 18

4 means of seperating mixtures

Answer 18

chromatography fitration distillation crystallisation

Question 19

What is filtration used for?

Answer 19

filtering insoluble particles from solvents-sand filtered from water using filter paper which let the water through but keeps sand in.

Question 20

What is crystallisation used for ?

Answer 20

To extract a soluble particle (solute) from a solvent eg salt from seawater.This occurs by heating the solution until crystals occur on the evaporation dish then when it is a saturated solution leave the the dish to evaporate out naturally to form crystals of the solute.

Question 21

What is simple distillation?

Answer 21

Simple Distillation is a separation technique used to separate a solvent from a mixture. For example, water can be separated from salt solution by distillation.
Simple Distillation involves boiling the mixture and then condensing the gas to produce a liquid. Simple Distillation is a separation technique used to separate liquid (the solvent) from a mixture and keep the liquid part. Distillation involves boiling the solution and then condensing the vapour back into a liquid by cooling it down.Eg.collecting both salt and water from sea water

Question 22

Why is fractional distillation used differently from simple distillation and what is it?

Answer 22

Some mixtures contain more than one liquid. If there are two different liquids with different boiling points, they can also be separated using distillation.
Ethanol boils at 78°C, whereas water boils at 100°C. A mixture of ethanol and water can be separated using fractional distillation. Since ethanol has a higher boiling point most of the evaporate will come up the fractionating tower which gets cooler the higher. A thermometer should say (which is at the top) when the top reaches ethanol boiling point. Then ethanol will rise up condense into liquid and be collected in a flask while any water that gets evaporated off gets instantly condensed as it reaches the top and fall back down into the original flask.It is more commonly used for seperating liquids such as crude oil.

Question 23

What is chromatography used for?

Answer 23

Paper chromatography is used to separate mixtures of soluble substances. These are often coloured substances such as food colourings, inks, dyes or plant pigments.

Question 24

Explain the chromatography phases.

Answer 24

Chromatography relies on two different ‘phases’:

the stationary phase, which in paper chromatography is very uniform, absorbent paper
the mobile phase is the solvent that moves through the paper, carrying different substances with it
The different dissolved substances in a mixture are attracted to the two phases in different proportions. This causes them to move at different rates through the paper.

Question 25

What do different results on a chromatogram show?

Answer 25

Separation by chromatography produces a chromatogram. A paper chromatogram can be used to distinguish between pure and impure substances: a pure substance produces one spot on the chromatogram an impure substance, or mixture, produces two or more spots.

Question 26

How do you identify similar substance in a chromatogram.

Answer 26

A paper chromatogram can also be used to identify substances by comparing them with known substances. Two substances are likely to be the same if: they produce the same number of spots, and these match in colour the spots travel the same distance up the paper

Question 27

Who discovered the idea of atoms?

Answer 27

John Dalton

Question 28

How did JJ thompson discover the electron?

Answer 28

He was applying high voltages to gases in low pressure in a vacuum and he realised that the glass was glowing in the positive end which meant thousand of negative particles were attracted to the positive end of the tube so he theorized electrons.

Question 29

What is the plum pudding model?

Answer 29

The model of atom where the atom was a sphere of positive charge dotted by negative electrons like plums in a pudding.

Question 30

What was the evidence for the nucleus

Answer 30

Hans Geiger and Ernest Marsden, directed a beam of alpha particles at a very thin gold leaf suspended in a vacuum.The vacuum is important because any deflection of the alpha particles would only be because of collisions with the gold foil and not due to collisions with air particles. Gold was used because it was the only metal that could be rolled out to be very, very thin without cracking.Since the gold foil was very thin, it was thought that the alpha particles could pass straight through it, or possibly puncture the foil. The scientists were very surprised when other things happened: most of the alpha particles did pass straight through the foil a small number of alpha particles were deflected by large angles (> 4°) as they passed through the foil a very small number of alpha particles came straight back off the foil The fact that most alpha particles went straight through the foil is evidence for the atom being mostly empty space. A small number of alpha particles being deflected at large angles suggested that there is a concentration of positive charge in the atom. Like charges repel, so the positive alpha particles were being repelled by positive charges. The very small number of alpha particles coming straight back suggested that the positive charge and mass are concentrated in a tiny volume in the atom (the nucleus). The tiny number of affected particles means the chance of being on that exact collision course was very small, therefore the 'target' being aimed at had to be equally tiny.

Question 31

What did Niels Bohr discover?

Answer 31

He noticed when heating atoms only gave specific amounts of energy.He then theorized that electrons were orbiting at set distances unlike rutherford nuclear model which makes them move in not set distances.

Question 32

Why were neutrons difficult to be discovered?

Answer 32

They have no charge therefore being undetectable.

Question 33

What did James Chadwick discover

Answer 33

the proton

Question 34

What are the two subatomic particles in the nucleus

Answer 34

Proton and Neutron

Question 35

What are charges of the subatomic particles?

Answer 35

Proton +1 Neutron) Electron-1

Question 36

What are the masses of the different sa particles?

Answer 36

Proton 1 Neutron 1 Electron 1/1836

Question 37

What is the atomic number?

Answer 37

The amount of protons

Question 38

What is the mass number?

Answer 38

The number of protons and neutrons

Question 39

How to find electrons using Atomic number

Answer 39

the electrons usually eill be the same amount.

Question 40

What is an isotope

Answer 40

An atom with a various propotion of neutrons but has the same chemical propeties

Question 41

how much electrons in each shell does in the first 20 elements

Answer 41

first 2 second 8 third 8 first 2

Question 42

What do the group number and the number of electrons on the valence shell share?

Answer 42

Same number and elements in the group will have the same properties as the other elements in their group because the way an element reacts is based on the elements on the outer shell.

Question 43

State 2 ways in which rutherford changed thomson's model of the atom

Answer 43

positive charge concentrated into very small volume at centre of atom (nucleus), electrons orbit nucleus

Question 44

How did bohr fix rutherfords model?

Answer 44

Energy emitted from electron transitions can only have certain fixed energies, so he refined the ‘orbiting electrons’ in Rutherford’s nuclear model to ‘orbiting electrons in energy levels (or shells) at fixed distances from the nucleus’.