Experimental techniques (p2)

A student investigates how the concentration of an acid affects the speed of reaction with a 0,5g mass of magnesium at 30^oC.

The student has a beaker, concentrated acid, water and the apparatus below.

Which pieces of apparatus does the student use?

• a balance

• a clock

• a measuring cylinder

• a thermometer

A student was provided with only a thermometer, a stopwatch and a beaker.

What could the student measure?

• 10.5g solid and 24.8cm³ liquid

• 10.5g solid and 25^oC

• 24.8cm³ liquid and 45 seconds

• 25^oC and 45 seconds

A student carries out an experiment to find how fast 3 cm pieces of magnesium ribbon dissolve in 10 cm³ samples of sulfuric acid at different temperatures?

What piece of apparatus does the student not need?

• balance

• measuring cylinder

• stop-clock

• thermometer

A student takes 2 g samples of calcium carbonate and adds them to 20 cm3 samples of dilute hydrochloric acid at different temperatures. She measures how long it takes for the effervescence (sủi bọt) to stop.

Which apparatus does she use?

• balance

• clock

• filter funnel

• measuring cylinder

• thermometer

P, Q, R and S are pieces of apparatus.

Which row describes the correct apparatus for the measurement made?

• P: the volume of acid added to alkali in a titration

• Q: 1cm³ of acid to add to calcium carbonate in a rate-determining experiment

• 75 cm³ of a gas given off in a rate - determining experiment

• 20 cm³ of alkali for use in a titration

During a reaction, the following changes take place.

1. The temperature rises.
2. A gas is given off.

Which apparatus is required to measure the rate of this reaction?

• balance and burette

• balance and gas syringe

• gas syringe and burette

• gas syringe and stop-clock

A mixture of ethanol and methanol are separated by fractional distillation. This method of separation depends on a difference in property X of these two alcohols.

What is property X?

• boiling point

• colour

• melting point

• solubility

A fruit drink coloured orange contains a dissolved mixture of red and yellow coluring agents. One of these colouring agents is suspected of being illegal.

Which method could be used to show the presence of this illegal colouring agent?

• chromatography

• distillation

• evaporation

• filtration

A student carries out an experiment to separate pure magnesium sulfate crystals.

The diagram shows the first stage of preparation.

He adds magnesium carbonate until no more reacts.

Which process should he use for the next stage?

• crystallisation

• evaporation

• filtration

• neutralisation

A student separate salt from a mixture of salt and sand.

What is the correct order of steps for the student to take?

• filter → evaporate → shake with water

• filter → shake with water→ evaporate

• shake with water → evaporate → filter

• shake with water → filter → evaporate