Edexcel GCSE Chemistry Paper 2 Higher June 2023 question paper 1CH0/2H

Butanol is a liquid fuel.

A student investigated the mass of butanol needed to increase the temperature of 100 cm³ of water by 1 °C.

The student used the following method.

step 1add 100 cm³ of water to a beaker

step 2 measure the mass of a spirit burner containing butanol

step 3 measure the initial temperature of the water in the beaker

step 4 place the spirit burner containing butanol under the beaker of water

step 5 light the wick of the burner and start to stir the water with the thermometer

step 6 stop heating the water when the temperature of the water has increased by 30 °C

step 7 remeasure the mass of the spirit burner containing butanol.

Figure 1 shows the apparatus used.

Figure 2 shows the student’s results.

In the student’s investigation, the temperature of the 100 cm³ water increased by 30 °C.

Calculate the mass of butanol needed to increase the temperature of the 100 cm³ water by 1 °C.

The student investigated the effect of changing the fuel on the mass of fuel needed to heat the water.

The student used an identical spirit burner filled with pentanol, another liquid fuel.

Give two variables that the student should keep the same in this investigation.

variable 1

variable 2

Suggest two improvements that the student could make to their apparatus so that more of the heat energy is transferred to the water.

improvement 1

improvement 2

A student used the apparatus shown in Figure 3 to investigate the reaction between marble chips and dilute hydrochloric acid.

The student recorded the volume of gas every minute as shown in Figure 4.

On the grid, plot the results shown in Figure 4.

Draw a curve of best fit.

Rate of reaction can be calculated using

Figure 5 shows the rates of reaction calculated from the results of this experiment.

The rate of reaction for the time interval 2 to 3 minutes is missing.

Calculate the rate of reaction for the time interval 2 to 3 minutes.

rate of reaction =_........ cm³min

State and explain what happens to the rate of reaction as the acid reacts with the marble chips in this experiment.

The student repeated the experiment using the same volume of acid and the same mass of marble chips but used smaller marble chips.

All other conditions remained the same.

The student found that the reaction with the smaller marble chips was faster to start with but produced the same volume of gas.

Using this information, draw a line on the grid to show the results for the reaction with the smaller marble chips.

Label this line ‘C’.

Figure 6 shows some information about the group 1 metals.

Explain, in terms of their electronic configurations, why these metals are placed in group 1 of the periodic table.

Which row shows two correct properties of group 1 metals?

The word equation for the reaction of potassium with bromine is

potassium + bromine potassium bromide

Add the missing state symbol and balance the equation for this reaction.

A sample of potassium contains three isotopes, potassium-39, potassium-40 and potassium-41.

Explain the meaning of the term isotopes.

This sample of potassium contains

93.25% potassium-39

0.02% potassium-40

6.73% potassium-41

Calculate the relative atomic mass of this sample of potassium.

Atoms, molecules, nanoparticles and protons are types of particle.

List these four types of particle in order of size from smallest to largest.

Nanoparticles have a large surface area to volume ratio.

Figure 7 shows a cube-shaped nanoparticle with sides of 90 nm.

Figure 7

What is 90 nm in metres?

Calculate the simplest surface area to volume ratio for the nanoparticle in Figure 7.

Show your working.

surface area to volume ratio = 1:_........

Figure 8 shows the structure of a molecule of tetrafluoroethene.

Tetrafluoroethene can form the polymer poly(tetrafluoroethene).

Draw a diagram to show the structure of the repeating unit of this polymer.

Poly(tetrafluoroethene) is also known as Teflon^TM.

State one use of poly(tetrafluoroethene) and explain how one of its properties makes it suitable for that use.

use

explanation

Figure 9 shows the percentage of three gases, X, Y and Z, in the Earth’s early atmosphere.

What is the name of gas Z ?

It is thought that small quantities of hydrogen sulfide, H₂S, were also in the Earth’s early atmosphere.

Draw the dot and cross diagram for a molecule of hydrogen sulfide.

Show outer electrons only.

Acid rain is caused by some pollutant gases present in the atmosphere.

Explain how impurities in fossil fuels can result in acid rain.

A student investigates the effect of acid rain on cress plants.

The student uses this method.

step 1 grow 20 cress plants in each of two dishes, A and B

step 2 water the cress plants in dish A with 10 cm³ of dilute hydrochloric acid with a pH of 2

step 3water the cress plants in dish B with 10 cm³ of pure water with a pH of 7

step 4 repeat steps 2 and 3 every day for one week

step 5 count how many plants are still alive after one week.

State what piece of equipment the student could use to measure the pH of each liquid.

Explain one improvement that the student could make to the method to make the results more valid.

Chlorine gas can be prepared by reacting concentrated hydrochloric acid with solid potassium manganate(VII).

Figure 10 shows the apparatus used.

Figure 11 shows the hazard symbols for concentrated hydrochloric acid, potassium manganate(VII) and chlorine gas.

Use the information in Figure 11 to help you answer (a)(i) and (a)(ii).

What are the hazards associated with potassium manganate(VII)?

Explain one precaution that should be taken when preparing the sample of chlorine gas.

precaution

reason

State the purpose of the delivery tube.

Suggest why damp blue litmus is placed at the top of the gas jar.

In the reaction, potassium manganate(VII), KMnO₄, reacts with hydrochloric acid to form manganese chloride, MnCl₂, potassium chloride, chlorine and water.

Write the balanced equation for the reaction.

Figure 12 shows the structure of the molecules of three organic compounds.

Each molecule in Figure 12 contains a different functional group.

Circle the alkene functional group in propene.

Propene reacts with bromine water.

Complete the equation for the reaction of propene with bromine by drawing the structure of a molecule of the product.

H H

H H

propene bromine product

Propanoic acid reacts with calcium carbonate, CaCO₃, to form calcium propanoate, Ca(C₂H₅COO)₂, and two other products.

Name the two other products.

*(b) Glucose, C₆H₁₂O₆, is a carbohydrate.

A dilute solution of ethanol can be produced from glucose by fermentation.

The dilute solution of ethanol can then be processed to form a concentrated solution of ethanol.

Describe how the fermentation of glucose is carried out and how the dilute solution of ethanol produced can then be processed to form a concentrated solution of ethanol.

You may include diagrams in your answer.

Ammonia can be produced from the reaction of hydrogen with nitrogen.

What is the percentage by mass of nitrogen in ammonia, NH₃?

(relative atomic masses: H = 1.0, N = 14)

The reaction between hydrogen and nitrogen is exothermic.

Figure 13 shows the reaction profile of this exothermic reaction.

Which arrow represents the activation energy for the reaction?

Describe what the reaction profile shows about the energy involved in bond breaking and bond making in this reaction.

Ammonia, NH₃, and silicon dioxide, SiO₂, are both compounds that are made of two non-metallic elements.

Ammonia has a boiling point of –33 °C. Silicon dioxide has a boiling point of 2230 °C.

Explain why the boiling points of ammonia and silicon dioxide are so different.

Crude oil is a mixture of hydrocarbons.

Crude oil can be separated into useful fractions by the process of fractional distillation in a fractionating column.

Figure 15 shows a fractionating column, the fractions obtained and the trend in viscosity of the fractions.

Which row shows the correct uses for bitumen, diesel oil and fuel oil?

Explain the trend in the viscosity of the fractions.

Hydrocarbon X was cracked to form one molecule of hexane, C₆H₁₄, and one molecule of alkene Y.

The relative formula mass of Y is 56. The empirical formula of Y is CH₂.

Deduce the molecular formula of hydrocarbon X.

Show your working.

(relative atomic masses: H = 1.0, C = 12)

*(c) Large quantities of methane are used as a fuel.

Figure 16 shows a Bunsen burner.

Methane can be used as fuel for the Bunsen burner.

The air-hole on the chimney of the Bunsen burner can be opened and closed.

Explain the effect of opening and closing the air-hole of the Bunsen burner on the products of combustion of methane and the harm that using large quantities of methane as a fuel can cause.

A student carried out a flame test on a sample of solid potassium chloride.

The student followed this method.

step 1 dip a dry wooden splint into water

step 2 then dip the wooden splint into the sample of potassium chloride

step 3 hold the wooden splint in a roaring Bunsen burner flame

step 4 observe the colour seen in the flame.

The student made the following observation and conclusion.

‘ I saw that the flame colour was yellow so the sample must contain sodium ions.’

Due to the way the student carried out the experiment, this is not a valid conclusion.

Explain one improvement that the student could make to their method to obtain a valid conclusion.

improvement

reason

What colour should the student have seen in the flame if the test had been carried out correctly?

A sample of the potassium chloride was also tested for chloride ions.

Describe the test for chloride ions.

A student was asked to test a sample of aluminium sulfate for sulfate ions.

The student needed 25 cm³ of barium chloride solution of concentration

Calculate the mass of barium chloride that must be dissolved in water to make 25 cm³ of solution of this concentration.

Give your answer to 2 significant figures.

When the barium chloride solution was added to the aluminium sulfate solution, a precipitate was formed.

The balanced equation for this reaction is

Write the ionic equation for this reaction.