periodic table test

Question 1

when were neutrons and electrons discovered?

Answer 1

19th century

Question 2

what were elements ordered in before the 19th century

Answer 2

by weight

Question 3

Give 3 differences between the physical properties of the elements in group 1 and those of the t-metals

Answer 3

1) Group one elements are soft and can be cut with a knife, t-metals are hard.
2) Group one elements have a low density and t-metals have high density
3) Group one elements have low melting points and t-metals have high melting points.

Question 4

what colour and state is chlorine?

Answer 4

green gas

Question 5

what colour and state is bromine?

Answer 5

brown liquid

Question 6

what colour and state is iodine?

Answer 6

grey solid

Question 7

what are group 7’s called?

Answer 7

halogens

Question 8

why are elements in group 7?

Answer 8

because they have 7 outer electrons

Question 9

what are the 4 differences between the chemical properties of the elements in group 1 and the t-metals.

Answer 9

1) Group one elements are reactive, t-metals are non-reactive
2) group one elements have colourless compound solutions or white solids, t-metals have colourful compounds
3) Group one elements have a single valency, t-metals have variable valencies.
4) Group one elements are not catalyst, t-metals are catalyst.

Question 10

why are molecule melting and boiling points so low?

Answer 10

Molecules have weak intermolecular
forces between them and it is these forces that are broken during melting
or boiling

Question 11

Halogens (like all molecules) have low melting and boiling
points because:

Answer 11

• they are simple molecules (molecular structure)
• little energy is needed to break
• weak intermolecular forces

Question 12

Melting and boiling points increase down group 7 because:

Answer 12

-the molecules get larger
-intermolecular forces get stronger (as there are more of them)
-more energy is needed to break them

Question 13

Halogens have similar chemical properties because:

Answer 13

they have same number of electrons (7) in their outer shell

Question 14

Group 0 ALL have full outer shells, this is why….

Answer 14

• they are all in the same group
• they are nonreactive

Question 15

why is helium used for balloons and blimps?

Answer 15

• its lighter than air
• it’s non-combustible

Question 16

why is argon (Ar) used for light-bulbs and not oxygen(O)?

Answer 16

• argon is non-reactive, the metal won’t burn
• oxygen is reactive, the metal will burn

Question 16

why is neon used for strip lights/neon lights?

Answer 16

it’s nonreactive

Question 17

how reactive is chlorine+lithium?

Answer 17

very

Question 18

how reactive is bromine+lithium?

Answer 18

moderate

Question 19

how reactive is iodine+lithium?

Answer 19

slow

Question 20

how reactive is astatine+lithium?

Answer 20

very slow

Question 21

Group 7 reactivity decreases down the group, the opposite of which group?

Answer 21

group 1

Question 22

Physical Properties of group 1

Answer 22

-Soft (can be cut with a knife)
-Low density (Li, Na and K float on water)
-Relatively low melting points and boiling points

Question 23

chemical Properties of group 1

Answer 23

-In reactions, they lose 1 outer electron to form +1 ions
-Similar chemical properties because all have 1 electron in
their outer shell
-This is shown in their reactions with O 2, Cl 2 and water

Question 24

group 1 reaction with Oxygen

Answer 24

Form white oxides eg sodium oxide word equation: sodium + oxygen =sodium oxide balanced equation: 4Na + O 2 = 2Na 2 O

Question 25

Give 3 reasons why argon (Ar) is used in crisp packets?

Answer 25

- it's non-reactive -it preserves

Question 26

Group 0 boiling point trend

Answer 26

The boiling point increases down the group (the negative numbers become less negative)

Question 27

why is helium (He) and not hydrogen (H2) used inside airships and party balloons?

Answer 27

- Helium is non-reactive and less dense than air - Hydrogen is less dense than air but very flammable

Question 28

what colour is the flame for lithium?

Answer 28

red

Question 29

what colour is the flame for pottassium?

Answer 29

purple

Question 30

what colour is the flame for sodium?

Answer 30

yellow

Question 31

what happens when group one reacts with chlorine

Answer 31

green gas (chlorine) fades white smoke/gas white solid

Question 32

what happens when group one reacts with water

Answer 32

Forms an alkaline solution (hydroxide) and hydrogen gas.

Question 33

Group 1 are called alkali metals because:

Answer 33

they react with water to form an alkaline solution

Question 34

what is the modern name for atomic weight?

Answer 34

relative atomic mass

Question 35

in the modern periodic table, the elements are arranged in order of what?

Answer 35

increasing atomic numbers

Question 36

what happens when sodium reacts with water?

Answer 36

-Fizzes more than lithium -moves across the surface -dissolves -UI turns purple -rolls into a ball

Question 37

what happens when pottasium reacts with water?

Answer 37

-Catches fire (lilac flame) -moves across surface -UI turns purple

Question 38

Reactivity increases down group 1 because:

Answer 38

-the atom gets bigger -the bigger the atom, the further away the last electron is from nucleus -Therefore, the attraction between the nucleus and the last electron gets weaker (makes outer e easier to be lost)

Question 39

why is chlorine more reactive than iodine

Answer 39

-higher in group 7 therfore smaller -closer to and more attracted to nucleus -incoming electron is much easier gained

Question 40

what do you put next to group 7 (hallogens when writing their short name)

Answer 40

a small 2 because they are diatomic elements