chemistry (chapter one) shells

Question 1

how many elements are there?

Answer 1

92

Question 2

what is an element?

Answer 2

a substance containing only one atom

Question 3

how many elements are naturally liquids?

Answer 3

2

Question 4

state one way of sorting elements into the periodic table

Answer 4

metals v non metals

Question 5

give three properties of a non metal

Answer 5

poor conductor of electricity, poor conductor of heat,dull, low density, brittle,not sonorous

Question 6

what is a chemical property?

Answer 6

Chemical properties describe the chemical reactions elements can undergo.

Question 7

. What 2 problems does acid rain cause?

Answer 7

. bad for trees and makes lakes acidic

Question 8

How can you tell what ‘group’ an element is in?

Answer 8

you check what vertical column its in

Question 9

what is density?

Answer 9

How much mass something has for its volume.

Question 10

How can you tell which ‘period’ an element is in?

Answer 10

You check which horizontal row it is in.

Question 11

What 2 characteristics do all group 1 elements have?

Answer 11

They are good conductors of electricity and heat. They are shiny when freshly cut.

Question 12

Group 1 elements are not reactive at all. True or false?

Answer 12

False – they are very reactive.

Question 13

What does chlorine do to bacteria?

Answer 13

Destroy it.

Question 14

What is another name for ‘group 7’ elements?

Answer 14

Halogens.

Question 15

Name 2 characteristics of group 7 elements?

Answer 15

Low melting points. Do not conduct electricity.

Question 16

What is the difference between the pattern shown for boiling point in group 7 vs group 1?

Answer 16

Group 7 – melting point increases from top to bottom. Group 1 – decreases from top to bottom.

Question 17

What are displacement reactions?

Answer 17

A displacement reaction occurs when a more reactive element displaces, or pushes out, a less reactive element from a compound.

Question 18

Name 5 ‘noble gases’.

Answer 18

Helium, neon, argon, krypton, xenon, and radon.

Question 19

Noble gases have very low melting and boiling points. True or false?

Answer 19

True.

Question 20

Can you see noble gases at room temperature?

Answer 20

No, they are colourless at room temperature.

Question 21

Where are the noble gases on the periodic table?

Answer 21

the furthest group on the right

Question 22

How do neon signs work?

Answer 22

Neon glows brightly when a high-voltage electric current passes through it.

Question 23

. Which 2 noble gases never take place in chemical reactions?

Answer 23

Helium and neon.

Question 24

Where can you find group 1 on the periodic table?

Answer 24

to the left of the stepped line