CIE Chemistry (US-0439): Specimen Questions with Answers 228 - 230 of 240

Question number: 228

Short Answer Question▾

Write in Short

A student followed the course of this reaction by measuring the volume of oxygen released over a period of time.

The diagram below shows some results that he obtained using hydrogen peroxide at three different concentrations.

Image of hydrogen peroxide

Image of Hydrogen Peroxide

Image of hydrogen peroxide

  1. Describe how the concentration of hydrogen peroxide affects the rate of this reaction.

…………………………………………………………………………………………………

Explanation

Concentration of Hydrogen per oxide affect the reaction by increasing the rate of reaction the hydrogen per oxide will be concentrated then time taken to complete the reaction will be less. Data is given below.

Concentration of Hydrogen

Concentration of Hydrogen

Concentration of Hydrogen

Question number: 229

MCQ▾

Question

When a Chalk piece is added to Vinegar, it ________.

Choices

Choice (4) Response

a.

Disintegrates

b.

Dissolves to from a solution

c.

Changes its colour to blue.

d.

Remains the same

Answer

a.

Explanation

When a Chalk (calcium carbonate) piece is added to Vinegar (acetic acid), it disintegrates.

Question number: 230

Short Answer Question▾

Write in Short

Describe a test, other than measuring pH, which can be carried out on both acid solutions to confirm the explanation given in (b) (i) for the different pH values of the two acids.

Complete the following equations for reactions of these two acids.

Explanation

.