Questão 1
Questão
What ion is present if a lilac flame is produced in a flame test?
Responda
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Lithium Li+
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Sodium Na+
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Potassium K+
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Calcium Ca2+
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Barium Ba2+
Questão 2
Questão
What ion is present if a blue precipitate is formed in the presence of sodium hydroxide?
Responda
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Iron (II) Fe2+
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Iron (III) Fe3+
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Copper Cu2+
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Barium Ba2+
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Magnesium Mg2+
Questão 3
Questão
What ion is present if a white precipitate is formed in the presence of sodium hydroxide which dissolves in excess sodium hydroxide?
Responda
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Sodium Na+
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Iron (III) Fe3+
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Aluminium Al3+
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Calcium Ca2+
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Magnesium Mg2+
Questão 4
Questão
Which test is used for detecting carbonate ions?
Responda
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Adding dilute nitric acid then silver nitrate
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Adding dilute hydrochloric acid and bubbling the gas through limewater
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Adding dilute hydrochloric acid then barium chloride
Questão 5
Questão
Which test is used for detecting halide ions?
Responda
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Adding dilute nitric acid then silver nitrate
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Adding dilute hydrochloric acid and bubbling the gas through limewater
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Adding dilute hydrochloric acid then barium chloride
Questão 6
Questão
Which test is used for detecting sulphate ions?
Responda
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Adding dilute nitric acid then silver nitrate
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Adding dilute hydrochloric acid and bubbling the gas through limewater
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Adding dilute hydrochloric acid then barium chloride
Questão 7
Questão
What would you use a pipette for in an acid-alkali titration?
Questão 8
Questão
What would you use a burette for in an acid-alkali titration?
Questão 9
Questão
How many cm^3 make up 1 dm^3?
Questão 10
Questão
True or false? When calculating the concentration of a substance in a titration, you have to divide the number of moles used by the volume of the solution.
Questão 11
Questão
True or false? The sodium hydroxide test is a type of quantitative chemical test.
Questão 12
Questão
What test is carried out to analyse DNA?
Responda
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Silver nitrate test
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Titration
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Gel electrophoresis
Questão 13
Questão
What is dynamic equilibrium?
Responda
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The point at which the reversible reaction stops
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The point at which the rate of forward reaction is equal to the rate of backward reaction
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The point at which a see-saw is balanced
Questão 14
Questão
True or false? If you increase the concentration of a reactant, more of the products will be formed in a reversible reaction.
Questão 15
Questão
If the forward reaction produces more molecules of gas than the backward reaction, what should you do to maximise the yield of products?
Responda
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Increase the pressure
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Decrease the pressure
Questão 16
Questão
If the forward reaction is endothermic, what should you do in order to maximise the yield of products?
Responda
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Increase the temperature
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Decrease the temperature
Questão 17
Questão
Which process is used to make ammonia?
Responda
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Bessemer process
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Contact process
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Haber-Bosch process
Questão 18
Questão
True or false? Unreacted gases in the Haber-Bosch process are not recycled.
Questão 19
Questão
True or false? The pressure in the Haber-Bosch process is 200atm because, although high pressure increases yield, it becomes increasingly difficult to find suitable storage containers.
Questão 20
Questão
True or false? The temperature of the Haber-Bosch process is 450°C because, although the reaction is exothermic and needs a lower temperature to maximise yield, too low temperatures stop the iron catalyst from working properly.