Paper 1- Inorganic Chemistry Flashcards
What are the Group 1 metals known as
alkali metals
What are simple reactions used to work out
- used to work out if an element is part of the same family as other elements
- elemnts of the same family will react in a similar way
alkali metal + water=
metal hydroxide + hydrogen
alkali metal + oxygen =
metal oxide
Do group 1 elements become more/ less reactive down the group
-more reactive
lithium + oxygen =
lithium oxide
potassium + oxygen =
potassium oxide
sodium + oxygen =
sodium oxide
Why do group 1 elements become more reactive as you go down the group
- group 1 has 1 electron in outer shell
- so as you go down the group the outermost electron becomes further away from the nucleus
- so attraction between outermost electron and nucleus becomes less
What are the Group 7 metals known as
The Halogens
What occurs as you go down group 7
- higher boiling point
- elements have a darker colour
- less reactive
What is chlorine
- fairly reactive,
- poisonous green gas
What is bromine
- poisonous red-brown liquid
- gives off orange vapour at room temp
What is iodine
- dark grey crystalline solid
- gives off purple vapour when heated
Why do group 7 elements become less reactive as you go down the group
- halogen atom needs to gain 1 electron
- the easier it is for the halogen atom to attract an electron, the more reactive the halogen will be
- it becomes harder to attract the extra electron to fill outer shell when its further away
- hence why as you go down group 7, halogens become less reactive
Definition of a displacement reaction
when a more reactive element displaces (pushes out0 a less reactive element from a compound
Definition of oxidation
a loss of electrons
Definition of reduction
a gain in electrons
Definition of oxidising agent
-accepts electrons and gets reduced
Definition of reducing agent
-donates electrons and gets oxidised
Give an example of a halogen displacement reaction
describe what is occurring in the reaction
chlorine + potassium iodide-> iodine + potassium chloride
-chlorine is more reactive than iodine so the iodine is displaced from the salt
- chlorine is reduced
- iodine is oxidised
Definition of a redox reaction
-reactions where reduction and oxidation happen at the same time
What are the 4 gases in the atmosphere
and what % of these gases are in the air
- 78% Nitrogen
- 21% Oxygen
- nearly 1% Argon
- 0.04% Carbon dioxide
What 2 things can be used to investigate the proportion of oxygen in the atmosphere
- iron
- phosphorus
How can iron be used to investigate the proportion of oxygen in the atmosphere
-describe the steps in the practical
- soak iron wool in acetic acid
- then push the wool into a measuring cylinder and invert the measuring cylinder into a beaker of water
- record starting positions of water using scale on measuring cylinder
- level of water in measuring cylinder will rise
- as iron reacts with oxygen in air to form iron oxide
- leave meausring cylinder for a week
- record finishing position of water
how do you calculate the % of oxygen in the atmosphere
start volume - final volume/ start volume x100
How can phosphorus be used to investigate the proportion of oxygen in the atmosphere
-describe the steps in the practical
- place phosphorus in tube and attach glass syringe at either end
- fill one syringe with air and leave the other empty
- heat phosphorus using syringes to pass air over it
- phosphorus will react with oxygen in air to make phosphorus oxide
- as it reacts the amount of air in syringe will decrease
- measuring start and final volumes of air using scale on one of the syringes
What is formed when an element is burned in the air
reacts with oxygen to form an oxide
How does magnesium react with oxygen
- burns with a bright white flame in air
- white powder is formed-
How does hydrogen react with oxygen
- very easily
- orangey/yellow flame
- only product = water
How does sulfur react with oxygen
- burns with a pale blue flame
- produces sulfur dioxide
What does the thermal decomposition of metal carbonates produce
carbon dioxide
metal oxide
What is copper carbonate
what will it decompose to form
- green powder
- will easily decompose to form carbon dioxide and copper oxide
How do you carry out a thermal decomposition experiment
- place copper carbonate in a test tube with a bung
- coming out of the test tube is a tube that is connected top another test tube which collects the CO2 gas
What is Carbon dioxide
a greenhouse gas