Edexcel GCSE Combined Science Paper 4: Chemistry 2 Foundation June 2024 question paper 1SC0/2CF

This question is about the metals and non-metals in period 3 of the periodic table.

Figure 1 shows some data about some of the elements in period 3.

Use the periodic table to answer these questions.

Give the name of the element in period 3 that is not shown in Figure 1.

Give the relative atomic mass of silicon.

State which metal and which non-metal in Figure 1 have the lowest melting points.

metal with lowest melting point

non-metal with lowest melting point

Alkali metals react with water to produce an alkaline solution and hydrogen gas.

A test tube of gas can be tested to see if the gas is hydrogen by putting a lighted splint at the top of the test tube.

A student suggests the following method to show that an alkaline solution and hydrogen gas are produced in this reaction.

step 1pour 150 cm³ water into the container shown in Figure 2

step 2 add a small piece of lithium to the water in the container shown in Figure 2

step 3 hold a lighted splint above the container

step 4 hold some damp red litmus paper above the mixture in the container

Give the name of the container shown in Figure 2.

A teacher says that step 3 and step 4 will not work to show that hydrogen gas and an alkaline solution are produced in the reaction.

Explain one change that could be made in each step to make the method work.

step 3_........

In one reaction the temperature of the reaction mixture decreases.

Which word describes this type of reaction?

In an experiment, a salt is dissolved in water.

The temperature change is measured.

Figure 3 shows the apparatus that is used.

State what is used to measure the temperature change in Figure 3.

State one reason for using the piece of equipment A in Figure 3.

A student suggests putting a lid on piece of equipment B.

State why this would help to give a more accurate value for the temperature change.

Four different salts, P, Q, R and S, are dissolved in water.

Figure 4 shows the starting temperature of the water and the final temperature of the solution after the salt dissolves.

Complete the table

• to show the temperature changes when salt R and salt S dissolve

• by placing a tick (✓) in the box, on the bottom row, for the salt that absorbs the most heat energy when it dissolves.

One of the salts dissolved is barium chloride, BaCl₂.

Barium chloride contains the chloride ion, Cl^–.

Give the formula of the barium ion in barium chloride.

Figure 5 shows the structure of one molecule of three different compounds, X, Y and Z.

The molecules of the compounds shown in Figure 5 all contain the same number of carbon atoms.

Give the number of carbon atoms in a molecule of compound X.

Compound X contains carbon and one other element.

Give the name of the other element in compound X.

Which of the compounds in Figure 5 is a hydrocarbon?

Which of the compounds in Figure 5 have the same molecular formula?

Figure 6 shows where fractions are produced in the fractional distillation of crude oil.

Complete the sentences about fractions obtained from crude oil.

The fraction with the smallest molecules is called_........ .

Compared to petrol, the boiling point of kerosene is_........ .

When petrol burns, one product is_........ .

When some impure hydrocarbon fuels are burned, sulfur dioxide is one of the products.

Some sulfur dioxide gas is dissolved in water to form solution W.

When solution W is added to sodium hydroxide solution of pH 12

• the pH changes

• the temperature increases.

Explain how the pH changes and why the temperature increases.

This question is about bromine.

Give the colour and physical state of bromine at room temperature.

colour_........

physical state_........

Bromine reacts with hydrogen to form hydrogen bromide.

Write the word equation for this reaction.

Hydrogen bromide dissolves in water to form a solution.

This solution of hydrogen bromide reacts with alkalis.

State the type of reaction that occurs when a solution of hydrogen bromide reacts with an alkali.

Bromine and the other halogens react with hot iron wool.

Figure 7 shows the relative speed of some of these reactions.

Fluorine also reacts with hot iron wool.

Use Figure 7 to predict the relative speed of this reaction.

Potassium bromide contains 32.8% potassium by mass.

Calculate the mass of potassium and the mass of bromine in 500 g potassium bromide.

mass of potassium =_........ g

mass of bromine =_........ g

A student investigates the reaction between marble chips and dilute hydrochloric acid.

The student measures the total volume of carbon dioxide gas produced each minute, for 10 minutes.

Figure 8 shows part of the apparatus used in the experiment.

Complete Figure 8 by drawing and labelling apparatus that could be used to collect and measure the volume of the carbon dioxide gas.

Figure 9 shows a graph of the results of the experiment.

A tangent has been drawn on the curve at a time of 3.5 minutes.

State the total volume of carbon dioxide produced in the first 3.5 minutes.

volume =_........ cm³

Using the tangent, calculate the rate of reaction at 3.5 minutes in cm³ per minute.

rate =_........ cm³ per minute

The student repeats the experiment using the same mass of smaller marble chips.

All other conditions remain the same.

Explain the effect on the rate of reaction of using smaller marble chips.

Which change would make the rate of reaction slower?

In this experiment the volume of carbon dioxide gas produced is measured.

Give a different way that the amount of carbon dioxide produced can be measured.

In this experiment there is an excess of dilute hydrochloric acid.

State what you would see in the conical flask at the end of the experiment.

This question is about the atmosphere.

Describe the test to show that a gas is oxygen.

Copper reacts with oxygen to form copper oxide.

2.100 g of copper will react completely with 0.529 g of oxygen.

In an experiment, 4.200 g of copper is heated with 50.000 g of oxygen until the reaction is complete.

Calculate the mass of oxygen remaining at the end of the experiment.

mass of oxygen =_........ g

Helium, neon and argon are all inert.

Explain, in terms of electrons, why these gases are inert.

Two pieces of steel can be joined by heating the metal pieces with a very hot flame.

This process is often carried out in an argon atmosphere rather than in air.

Which property makes argon gas suitable for this use?

*(d) Figure 10 shows how plant life and the atmosphere of Earth have changed over time.

Explain the effect that plant life has had on the Earth’s atmosphere and the temperature of the Earth.

You should refer to the information in Figure 10 including

• the plant life

• the amounts of carbon dioxide

• the amounts of oxygen