PAPER 1- WRONG QUESTIONS Flashcards
☀️ element containing a basic oxide (1 mark):
copper
🧪 is iodine a solid or liquid at room temperature (1 mark)?
solid
🧮 how to calculate relative atomic mass (3 marks):
(number of neutrons x percentage abundance) + (number of neutrons x percentage abundance) / 100
💦 process used to obtain pure water from sugar solution (1 mark):
simple distillation
explain the purpose of a condenser (2 marks):
- steam is cooled
- condenses in the condenser
🔥 2 products of incomplete combustion (2 marks):
- carbon
- carbon monoxide
🍃 discuss the environmental problems caused by burying polymers in landfill and burning them to release heat energy (3 marks):
- landfill- will always remain
- because they are unreactive
- burning them releases greenhouse gases which contributes to global warming
3 observations made when lithium reacts with water (3 marks):
- effervescence
- fast moving
- gets smaller
- floats
reason to clean rod before conducting flame test (2 marks):
- to remove any ions on the wire
- which may affect the colour of the flame
colour of flame when sodium ions are present:
yellow
colour of flame when lithium ions are present:
red
colour of flame when potassium ion are present:
purple
colour of flame when copper ions are present:
green/ turquoise
colour of flame when calcium ions are present:
orange- red
ammonium gas tests (3 marks):
- add sodium hydroxide solution and warm
- test the gas with damp red litmus paper
- will turn blue if ammonium ions are present
sulfate ions tests (3 marks):
- add dilute hydrochloric/ nitric acid
- add barium chloride solution
- will form a white precipitate if sulphate ions are present
🧪 purpose of cotton wool in a flask (1 mark):
- prevent acid from splashing out
test results when using sodium hydroxide:
- blue- copper
- green- iron
