Unit2Topic1 - Reactivity Series Of Metals

Question 1

Equation for metals reacting with air

Answer 1

metal + oxygen -> metal oxide

Question 2

Equation for metals reacting with water

Answer 2

metal + acid -> metal hydroxide + hydrogen

Question 3

Equation for metals reacting with steam

Answer 3

metal + steam -> metal oxide + hydrogen

Question 4

Equation for metals reacting with acids

Answer 4

metal + acid -> salt + hydrogen

Question 5

K and Na when left in air

Answer 5

Soft, can be cut easily with a knife to give a shiny surface that quickly tarnishes.

Question 6

Ca, Mg, Al and Zn when left in air

Answer 6

React slowly, forming an oxide layer

Question 7

Fe and Cu when left in air

Answer 7

Oxide layer is easily rubbed off

Question 8

K when heated in air

Answer 8

Burns with a lilac flame

Question 9

Na when heated in air

Answer 9

Burns with bright yellow flame

Question 10

Apparatus used when heating K and Na in air

Answer 10

deflagrating spoon

Question 11

Ca when heated in air

Answer 11

Burns with brick red flame

Question 12

Mg when heated in air

Answer 12

Burns with bright white flame, leaving a white ash

Question 13

Al when heated in air

Answer 13

Sheets of Al don’t burn easily. Powdered Al burns with white sparks, leaving white solid.

Question 14

Zn when heated in air

Answer 14

Burns leaving yellow solid which when cooled changes to white.

Question 15

Fe when heated in air

Answer 15

Sheets of Fe don’t burn easily. Fe wool or Fe filings burn with yellow/orange sparks, forming black solid

Question 16

Cu when heated in air

Answer 16

Sheets of Cu quickly form black copper oxide layer. The black layer will form without heating.

Question 17

Apparatus used when heating Ca, Mg, Al, Zn, Fe and Cu in air

Answer 17

Hold over Bunsen flame with tongs or place in crucible on a tripod over Bunsen

Question 18

Reactions between metals and water are …

Answer 18

Exothermic: heat energy is given out and the solution warms up/ test tube feels warm.

Question 19

Why do some metals have to be stored under oil? E.g. Li, Na, K

Answer 19

They’re very reactive with oxygen and water and are therefore stored under oil to prevent them being in contact with oxygen and moisture in the air

Question 20

K reaction in water

Answer 20

Floats
Moves rapidly around surface
Bursts into lilac flame
Bubbles of gas released 
Colourless solution formed

Question 21

Na reaction in water

Answer 21

Floats
Moves rapidly around surface
So much heat released that Na melts into a sphere of molten metal that may burn with yellow flame
Colourless solution formed

Question 22

Further tests in trough of water where K and Na have reacted

Answer 22

Solution changes Universal indicator from green to blue

Question 23

Ca reaction in water

Answer 23

Ca granules will sink initially
Bubbles of gas
Beaker feels warm to touch as heat is evolved

Question 24

Mg reaction in water

Answer 24

Very few bubbles observed even after leaving for several days

Question 25

Al, Zn, Fe, Cu reactions in water

Answer 25

No reaction. | Fe will rust after a few days

Question 26

Further tests after reacting Ca, Mg, Al, Zn, Fe and Cu in water

Answer 26

Gas collected in test tube burns with a squeaky pop.

Question 27

Chemical formula for steam

Answer 27

H2O (g)

Question 28

Mg reaction with steam

Answer 28

Reacts when heated Produces very bright white light White powder remains

Question 29

Al reaction with steam

Answer 29

Al foil will not react Small pieces will react when oxide layer is taken off Al powder reacts when heated to form a white powder

Question 30

Zn reaction with steam

Answer 30

Reacts when heated Glows as steam is passed over producing a yellow powder Yellow powder becomes white when cooled

Question 31

Fe reaction with steam

Answer 31

Fe must be heated until it glows red before the steam is passed over Reacts to form a black solid

Question 32

Further test after reacting Mg, Al, Zn and Fe in steam

Answer 32

Gas burns with squeaky pop

Question 33

Ca, Mg, Al, Zn reactions with acid

Answer 33

Bubbles of gas Metal disappears quickly Colourless solution formed Test tube feels warm to the touch as heat is evolved Rate of production of bubbles increases as you go up reactivity series

Question 34

Aluminium reacting with acid

Answer 34

Powdered Al is used as Al oxide layer adheres to surface of Al and protects it from reaction with acid. Al foil can be used if Al oxide layer is removed with scouring pad.

Question 35

Cu reaction in acid

Answer 35

No reaction - copper is very unreactive

Question 36

Why is the reaction between zinc and dilute HCl often used to produce hydrogen gas in a school laboratory?

Answer 36

Zinc metal reacts with HCl and gives a steady stream of gas, not too fast, not too slow

Question 37

What is a displacement reaction?

Answer 37

A displacement reaction is one where a more reactive element displaces a less reactive element from its compound

Question 38

Reactivity series

Answer 38

``` Potassium (please) Sodium (send) Lithium (little) Calcium (Charlie's) Magnesium (monkeys) Aluminium (and) Zinc (zebras) Iron (in) Tin (tall) Lead (lead) Copper (cages) Silver (securely) Gold (guarded) ```