Atomic Structure And Periodic Table

Question 1

What is the mass of an atom?

Answer 1

0.1 nanometers

Question 2

How can you determine what type an atom is?

Answer 2

The number of protons

Question 3

What is the element in the top box?

Answer 3

Hydrogen

Question 4

How many different elements are there?

Answer 4

100

Question 5

What are isotopes

Answer 5

Atoms with the same number of protons but different neutrons

Question 6

Describe the reactivity in group 1 elements

Answer 6

Reactivity increases down the group
Need to lose an electron as they are metals
Shielding increases
Meaning molecular size increases
Meaning intermolecular forces decrease

Question 7

What is a mixture?

Answer 7

A substance that isn’t chemically joined and can have elements or compounds or both

Question 8

How would we use chromatography to separate mixtures?

Answer 8

• Draw a line in pencil at the bottom of the filer paper so it doesn’t dissolve or travel
• add a dot or dots of ink to the line and place the bottom in the water. Don’t add the ink directly to the water otherwise it would dissolve and sometimes the compound doesn’t dissolve so ethanol may be used
• each pigment will travel up the paper at different rates so separates ink
• if ink is insoluable it stay on the baseline
• when nearly reached the top, leave to dry
  This is called a chromatogram

Question 9

How would we separate insoluable mixtures

Answer 9

Filtration is used as the larger molecules of the solid won’t fit through the filer paper so

Question 10

How would we separate insoluable mixtures

Answer 10

Filtration is used as the larger molecules of the solid won’t fit through the filer paper

Question 11

How would you separate solvable solids

Answer 11

Evaporation
- pour solution into dish
- slowly heat solution
- solution gets more concentrated
- eventually crystals should form and keep heating until dry crystals

Crystallisation
1. Pour the solution into dish and gently heat
- as it becomes more concentrated, crystals form
- take off heat and cool
- crystals form
- filtrate solution
- leave to dry

Question 12

How would you separate rocksalt?

Answer 12

Sand - insolvable
Salt - soluable

Crush mixture so salt dissolved easily
Dissolve salt in water by stirring
Filter sand
Evaporate solution to make salt crystals

Question 13

How would you separate solutions

Answer 13

1. Evaporate solution
2. Different solutions should have different melting points and boiling points so lower bp evaporates first
3. Vapour is cooled, condensed and collected

Question 14

What is a con of simple distillation?

Answer 14

Only works for solutions with very different melting points and boiling points