Alkali metals

Question 1

Give the name for Group 1

Answer 1

Alkali metals

Question 2

How many electrons do all of the group 1 metals have in their outer energy level

Answer 2

All group 1 metals have 1 electron in their outer energy level

Question 3

State the states of the group 1 metals at room temperature

Answer 3

All group 1 metals are solids at room temperature

Question 4

What is the temperature of room temperature

Answer 4

Room temperature is approximately 25 degrees celcius

Question 5

List some physical properties of the Group 1 metals

Answer 5

soft
low melting points
malleable
ductile
good conductors of heat
good conductors of electricity
low density

Question 6

How many alkali metals are less dense than water and what does this mean

Answer 6

The first three alkali metals are less dense than water.
This means that the first three alkali metals can float on water

Question 7

What is the trend in melting points in Group 1

Answer 7

Melting points decrease down the group as the metallic bonds between the atoms are weakened. This is because moving down the group, the atoms get larger, which means there is more shielding, which means the bonds between the atoms are weakened

Question 8

What is the trend in boiling points in Group 1

Answer 8

Boiling points decrease down the group

Question 9

What is the trend in reactivity in Group 1

Answer 9

Reactivity increases down the group

Question 10

What is the trend in relative atomic mass in Group 1

Answer 10

The relative atomic mass increases down the group

Question 11

Describe how lithium reacts with water

Answer 11

Effervescence
moves on the surface
Universal indicator has turned purple/colour of the indicator is darker near the lithium
The metal reduces in size and goes into the solution

Question 12

Describe how sodium reacts with water

Answer 12

Effervescence
Sodium melts into a sphere
Sodium moves on the surface
Universal indicator has turned purple/colour of the indicator is darker near the lithium
The metal reduces in size and goes into the solution

Question 13

Describe how sodium reacts with water

Answer 13

Effervescence
Potassium moves on the surface
Potassium ignites to give a lilac flame
Universal indicator has turned purple/colour of the indicator is darker near the lithium
The metal reduces in size and goes into the solution

Question 14

Describe how caesium reacts with water

Answer 14

Caesium reacts explosively with water.

Question 15

When Group 1 metals react, what happens to the Group 1 metal atoms in terms of electrons
Where do these electrons go
What type of compound is formed

Answer 15

Group 1 metals lose their outer electron to form 1+ ions
The electron was transferred to the substance it is reacting with
An ionic compound is formed.

Question 16

Why are alkali metals called Alkali metals

Answer 16

Alkali metals are called Alkali metals because they react with water to form alkaline solutions

Question 17

When an alkali metal reacts with water why is there fizzing

Answer 17

There is fizzing as hydrogen gas is being produced in the reaction

Question 18

When an alkali metal reacts with water why does the metal move over the surface of the water

Answer 18

Alkali have a low density so they can sit on the surface of the water, it is the hydrogen gas that propels the metal

Question 19

When an alkali metal reacts with water why does the universal indicator go purple

Answer 19

When an alkali metal reacts with water the universal indicator goes purple because an alkali is produced in the solution

Question 20

When an potassium reacts with water why does it ignite to give a lilac flame

Answer 20

Potassium is more reactive and the heat ignites the hydrogen gas to give a characteristic lilac flame

Question 21

When an alkali metal reacts with sodium why does sodium melt into a sphere

Answer 21

Sodium melts into a sphere as the heat generated from the reaction melts the sodium

Question 22

When an alkali metal reacts with water why does the metal reduce in size and go into the solution

Answer 22

The metal reacts and goes into the solution as a soluble alkali is formed.

Question 23

When alkali metals react with water what colour is the solution that is formed

Answer 23

When alkali metals react with water the solution produced is colourless.
The hydroxides of the alkali metals are all soluble in water

Question 24

Describe what happens when the alkali metals are heated in chlorine gas

Answer 24

They react vigorously when heated in chlorine gas to form white metal chloride salts which are white solids

Question 25

Can metal chlorides dissolve in water, if so what do they produce

Answer 25

Metal chlorides dissolve in water to form colourless solutions

Question 26

When lithium is exposed to the air why does it tarnish

Answer 26

When fresh lithium is cut and exposed to air, it tarnishes because the lithium is reacting with the oxygen to form a layer of lithium oxide.

Question 27

What do alkali metals produce when they burn in oxygen gas

Answer 27

When alkali metals burn in oxygen gas, they form white smoke of their oxides (the smoke is the compound)

Question 28

Give an observation of when lithium burns in oxygen

Answer 28

Lithium burns with a red flame to produce a white solid

Question 29

Give an observation of when sodium burns in oxygen

Answer 29

Sodium burns with a yellow-orange flame to give a white solid

Question 30

Give an observation of when potassium burns in oxygen

Answer 30

Potassium burns with a purple flame to give a white solid

Question 31

Explain the trend in reactivity of Group 1

Answer 31

Going down the group, the atoms become larger
The distance between the nucleus and the outer electron is greater, meaning it has more electron shells.
This results in increased shielding, which means the electrostatic attraction between the nucleus and the outer electron is weaker
Therefore, the outer electron is lost more easily.

Question 32

Why is sodium more reactive than lithium

Answer 32

A sodium atom is larger than a lithium atom

This means that the distance between sodium’s nucleus and it’s outer electron is greater than the distance between lithium’s nucleus and outer electron, which means that sodium has more electron shells than lithium.

This results in more shielding being experienced by sodium than lithium , which means that the electrostatic attraction between sodium’s nucleus and outer electron is weaker than the attraction between lithium’s nucleus and outer electron,

Therefore, sodium’s outer electron is lost more easily

Question 33

What do alkali metal produce when they react with water

Answer 33

When alkali metals react with water they form a metal hydroxide and hydogen

Question 34

Complete the sentence:
Group 1 metals react with water forming an ______ solution and Hydrogen gas

Answer 34

Group 1 metals react with water forming an alkaline solution and Hydrogen gas

Question 35

Define group

Answer 35

A group is a column in the periodic table where elements are arranged based on how many electrons are in their outer shell. The elements in a group share similar chemical properties

Question 36

Define period

Answer 36

A period is a row on the periodic table where elements are arranged based on how many electron shell they have