Cambridge IGCSE Chemistry - 0620 - Core Paper 1 2011 Winter Zone 2

In which substance are the particles close together and slowly moving past each other?

The diagram shows the electronic structures of atoms P and Q.

P and Q combine to form a molecule. What is the formula of this molecule?

A student was provided with only a thermometer, a stopwatch and a beaker.
What could the student measure?

Two isotopes of helium are $\frac{3}{2} \text{He}$ and $\frac{4}{2} \text{He}$.
Which two diagrams show the arrangement of particles in these two isotopes?

Mixture 1 contains sand and water.
Mixture 2 contains salt and water.
Which method of separation could be used to obtain each of the required products from each mixture?
[Table_1]

The relative formula mass, $M_r$, of copper(II) sulfate, CuSO$_4$, is 160.
Which mass of sulfur is present in 160g of copper(II) sulfate?

Two elements, represented by ⚪ and ⚫, form a compound. Which diagram shows molecules of the compound?

The table describes the structures of four particles.

[Table_1]

What are the correct values of $X$, $Y$ and $Z$?

Metals could be extracted from their molten chlorides using electrolysis. Which substances are formed at each electrode? [Table_1]

The diagram shows a section of an overhead power cable.
Which statement explains why a particular substance is used?

Concentrated aqueous potassium bromide solution is electrolysed using inert electrodes. The ions present in the solution are $K^+$, $Br^-$, $H^+$ and $OH^-$. To which electrodes are the ions attracted during this electrolysis? [Table_1]

The sign ⇌ is used in some equations to show that a reaction is reversible.
Two incomplete equations are given.

[Table_1]

For which of these reactions can a ⇌ sign be correctly used to complete the equation?

Which fuel needs oxygen in order to produce heat energy and which type of reaction produces the energy?
[Table_1]

Some reactions are listed.
methane + oxygen → carbon dioxide + water
sodium + water → sodium hydroxide + hydrogen
magnesium + hydrochloric acid → magnesium chloride + hydrogen
Which word correctly describes all of these reactions?

Which type of reaction always forms a salt and water?

An experiment to determine the rate of a chemical reaction could be carried out using the apparatus shown. Which reaction is being studied?

Copper(II) carbonate reacts with dilute sulfuric acid.
$\text{CuCO}_3(s) + \text{H}_2\text{SO}_4(aq) \rightarrow \text{CuSO}_4(aq) + \text{CO}_2(g) + \text{H}_2\text{O}(l)$
The speed of the reaction can be changed by varying the conditions.
Which conditions would always increase the speed of this chemical reaction?
1. Increase the concentration of the reactants.
2. Increase the size of the pieces of copper(II) carbonate.
3. Increase the temperature.
4. Increase the volume of sulfuric acid.

The table shows some properties of two elements in Group VII of the Periodic Table.
[Table_1]
Which properties is fluorine likely to have?

Statement 1: Helium is a reactive gas.
Statement 2: Helium can be used to fill balloons.
Which is correct?

An alloy contains copper and zinc.
Some of the zinc has become oxidised to zinc oxide.
What is the result of adding an excess of dilute sulfuric acid to the alloy?

An element has the following properties:
• It forms coloured compounds.
• It acts as a catalyst.
• It melts at $1539^\circ \text{C}$.
In which part of the Periodic Table is the element found?

The results of three tests on a solution of compound X are shown.
[Table_1]
What is compound X?

Which property is not characteristic of a base?

A liquid turns white anhydrous copper sulfate blue and has a boiling point of 103°C. Which could be the identity of the liquid?

Alloy X is strong and has a low density.
Alloy Y is heavy but is resistant to corrosion.
Which could be uses of X and Y?
[Table_1]

Which statements are correct?
1 Metals are often used in the form of alloys.
2 Stainless steel is an alloy of iron.
3 Alloys always contain more than two metals.

Which statement is true about all metals?

A metal is extracted from hematite, its oxide ore. What is the metal and how is the oxide reduced? [Table_1]

A chemical engineer plans to produce hydrochloric acid.
Which metal is best for the reaction container?

When sodium reacts with water, a solution and a gas are produced. The solution is tested with litmus paper and the gas is tested with a splint. What happens to the litmus paper and to the splint?

Iron is a metal that rusts in the presence of oxygen and water.
Mild steel is used for ......1...... and is prevented from rusting by ......2...... .
Stainless steel is prevented from rusting by ......3...... it with another metal.
Which words correctly complete gaps 1, 2 and 3?
[Table_1]

Dry air is passed over hot copper until all the oxygen has reacted.
The volume of gas at the end of the reaction is 120 cm³.
What is the starting volume of dry air?

In which row is the air pollutant not correctly matched with its source?
[Table_1]

Which pollutant gas is produced by the decomposition of vegetation?

Which combination of chemical compounds could be used to produce the fertiliser shown?

The diagram represents the molecule of an organic compound.
What is the name of the compound?

When glucose is fermented, ethanol is formed together with

The table shows the composition of four different types of petroleum (crude oil). [Table_1]
Which type of petroleum is best for the motor vehicle industry?

Which pair of compounds are members of the same homologous series?

Petroleum is a very important raw material that is separated into more useful products. Which terms describe petroleum and the method used to separate it?
[Table_1]