Hydrogen peroxide decomposes to form water and oxygen - Edexcel - GCSE Chemistry Combined Science - Question 2 - 2018 - Paper 1
Question 2
Hydrogen peroxide decomposes to form water and oxygen.
The rate of this reaction can be found by measuring the volume of oxygen formed after different time interval... show full transcript
Worked Solution & Example Answer:Hydrogen peroxide decomposes to form water and oxygen - Edexcel - GCSE Chemistry Combined Science - Question 2 - 2018 - Paper 1
Step 1
State the name of the piece of apparatus labelled Z in Figure 3.
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Answer
The piece of apparatus labelled Z in Figure 3 is a gas syringe. This device is used to accurately measure the volume of gas produced in chemical reactions.
Step 2
Explain what happens to the glowing splint when it is placed in the test tube.
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Answer
When a glowing splint is placed in the test tube that contains oxygen, it will rekindle or reignite. This is because oxygen supports combustion, causing the splint to burn brighter.
Step 3
Identify the correct statements about the reaction.
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Answer
The only correct answer is B: water and oxygen are the only products of the reaction. Other options are incorrect as they either do not describe the reaction accurately or misunderstand the role of catalysts.
Step 4
Describe the filtration process used in this experiment.
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Answer
To effectively remove water from the mixture, dry the filter paper and catalyst before measuring their mass. This ensures that the mass obtained is accurate and does not include water.
Step 5
Discuss the effect of changing the surface area of the catalyst on the reaction rate.
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Answer
If the surface area of the catalyst is increased, the reaction rate would generally increase. This happens because a larger surface area allows more collisions between the reactants and the catalyst.
Step 6
Write a balanced chemical equation for the decomposition of hydrogen peroxide.
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Answer
The balanced chemical equation for the decomposition of hydrogen peroxide is:
ightarrow 2H_2O(l) + O_2(g)$$
In this equation, the physical states of the substances are indicated as liquid (l) for water and gas (g) for oxygen.
