1C Jan 2015 Flashcards
What are isotopes?
Same atomic numbers different mass numbers.
Describe a chemical test to show that the colourless liquid contains water.
anhydrous copper sulphate turns blue
Describe a physical test to show that the colourless liquid is pure water.
Measure boiling point = 100C
Test for ammonium ions?
Add sodium hydroxide, gas given off is ammonia and it will turn litmus paper blue.
When showing that a substance contains chloride ions why do you add dilute nitric acid?
To remove carbonate ions.
What do you add to see if a substance contains chloride ions?
Silver nitrate.
Describe how crude oil is separated into fractions in industry.
Fractional distillation. Crude oil is heated. Cooler at top of tower, hotter a bottom. Fractions condense at different heights as they have different boiling points.
Characteristics of members of a homologous series.
Similar chemical properties, same functional group, trend in physical properties.
Why is carbon monoxide poisonous?
Reduces the capacity of blood to carry oxygen.
What is meant by the term biodegrade?
Breaks down.
What property prevents addition polymers from easily biodegrading?
Unreactive.
Describe the precipitation method.
Add solutions together, stir, filter, wash with water, dry with filter paper.
What is wrong with this? 2Br- + 2e- -> 2Br
Electrons should be on right and it should say Br2.
Why won’t electricity run through solution when electrolysis is turned off?
Ions stop moving.
What colour is phenolphthalein in a neutral substance?
Colourless.
