Periodic Table

Question 1

How did they organise the elements before they organised them to what?

Answer 1

Atomic mass

Now: physical state and chemical properties and relative atomic mass

Question 2

Why was newlands work criticised?

Answer 2

• groups contained elects that didn’t have similar properties
• mixed up metals and no metals
• didn’t leave gaps for more elects to be discovered

Question 3

What did Mendeleev do differently to Newland?

Answer 3

Put elements in order of mass but left big gaps

Question 4

What are the elements ordered in now?

Answer 4

Electronic structures - their energy levels

Question 5

Why do metals that go further down group 1 become reactive?

Answer 5

Nucleus further away from electrons - less attraction and more shielding, electron is in a higher energy level is more easily lost

Question 6

What does a increased distance and shielding mean?

Answer 6

Higher energy level is likely to gain electron because there’s less attraction from nucleus - why group 7 elements when you go down the group

Question 7

As you go doen group 1 the elements become…?

Answer 7

More reactive-outer electron more easily lost because its further away from nucleus
Have lower melting and boiling points

Question 8

What elements react vigorously in water? What do they produce?

Answer 8

Lithium sodium potassium

Hydrogen

Question 9

What are group 7 elements called?

Answer 9

Halogens

Question 10

As you go down group 7 the elements become…?

Answer 10

Less reactive - harder to gain outer electron

Higher melting and boiling point

Question 11

What do the halogens form when they ionically bond?

Answer 11

1- ions called halides

Question 12

A more reactive halogen can…? from a…?

Answer 12

Displace a less reactive halogen from an aqueous solution of its salt

Question 13

What are the transition metals?

Answer 13

Metals between group 2 and 3

Question 14

What properties do transition metals have?

Answer 14

• good conductors
• dense, strong, shiny
• less reactive
• higher boiling points and stronger than group 1

Question 15

What do transition metals make?

Answer 15

Good catalysts eg. Iron in the harder process

Question 16

what is meant by activation energy?

Answer 16

the energy needed for the reaction to take place

Question 17

why is it good to use a calorimeter when measuring energy?

Answer 17

because it is metal no glass therefore it conducts the heat from the fuel better

Question 18

why should you stir the water heating by the fuel when measuring the energy?

Answer 18

so the heat is evenly distributed around the container

Question 19

why do we use a polystyrene cup when measuring energy?

Answer 19

because it’s a good insulator so less heat escapes making it more accurate

Question 20

how could you improve the experiment with the polystyrene cup?

Answer 20

put a lid on it to reduce heat loss to air

stir the reaction to make sure temperature changes are evenly spread through the solution

Question 21

speed = ?

Answer 21

distance / time

Question 22

in distance time graph the gradient equals?

Answer 22

speed

Question 23

flat sections in a distance time graph mean?

Answer 23

it’s stationary

Question 24

downhill sections in a distance time graph means what?

Answer 24

it’s going back towards the starting point

Question 25

what does the gradient mean in a velocity time graph?

Answer 25

acceleration

Question 26

flat sections in a velocity time graph mean?

Answer 26

steady speed