Cambridge IGCSE Chemistry - 0620 - Core Paper 1 2012 Winter Zone 1

What are the processes W, X, Y and Z in the following diagram?

solid \leftrightarrow liquid \leftrightarrow gas

A mixture of sulfur and iron filings needs to be separated. The solubilities of sulfur and iron filings in water and carbon disulfide are shown in the table below.

[Table_1]

What are possible methods of separating the sulfur and iron filings?

Part of the instructions in an experiment reads as follows.
Quickly add 50 cm$^3$ of acid.
What is the best piece of apparatus to use?

Which statements comparing the properties of electrons, neutrons and protons are correct?
[Table_1: neutrons and protons are both heavier than electrons, only electrons and neutrons are charged]

Which row gives the number of electrons in the outer electron shell of fluorine and of neon?
[Table_1]

In the molecules CH₄, HCl and H₂O, which atoms use all of their outer shell electrons in bonding?

The table shows the electronic structures of four atoms.
[Table_1]
Which two atoms combine to form an ionic compound?

A compound has the formula CH$_3$CO$_2$H.
How should the relative molecular mass, $M_r$, of this compound be calculated?

The diagram shows the electrolysis of concentrated aqueous sodium chloride. What is produced at each of the electrodes?

The diagram shows an electrolysis experiment using metals X and Y as electrodes.

One of the metals becomes coated with copper. Which metal becomes coated and which aqueous solution is used?

The diagrams show the difference in energies of the reactants and products in two types of reaction.
[Image_1: diagram1 showing energy of products higher than reactants, diagram2 showing energy of reactants higher than products]
Which diagram and which type of energy change apply to a fuel burning in air?

The diagram shows a match.

By striking the match, a chemical reaction takes place.
Which statements about the chemical reaction are correct?
[Table_1]

Separate samples of anhydrous and hydrated copper(II) sulfate are heated. Which shows the correct colour changes?
[Table_1]

Which change is an oxidation?

Which change does not increase the speed of reaction between zinc and hydrochloric acid?

Which of these pairs of aqueous ions \textbf{both} react with dilute sulfuric acid to give a visible result?

Element X forms an acidic, covalent oxide.
Which row shows how many electrons there could be in the outer shell of an atom of X?
[Table_1]

Barium hydroxide is an alkali. It reacts with hydrochloric acid.
How does the pH of the hydrochloric acid change as an excess of aqueous barium hydroxide is added?

A compound is a salt if it

The diagram shows an outline of the Periodic Table.
Which of the elements U, V, W, X and Y would react together in the ratio of 1:1?

The element rubidium, Rb, is immediately below potassium in the Periodic Table. It reacts with bromine to form the compound rubidium bromide. Which descriptions of this compound are correct?
[Table_1]

The table gives information about four elements.
Which element is a transition metal?
[Table_1]

Why are weather balloons filled with helium rather than hydrogen?

Some properties of aluminium are listed.
1. It has mechanical strength.
2. It conducts heat.
3. It is resistant to corrosion.
4. It has a low density.
Which properties make aluminium useful for making the bodies of aircraft?

Brass is used in electrical equipment. It contains two ......1...... elements. Together they form ......2...... .
Which words correctly complete gaps 1 and 2? [Table_1]

The Basic Oxygen Process converts iron into steel. In step 1, oxygen is blown into impure molten iron. In step 2, oxides are removed by reaction with calcium oxide. Which chemical reaction takes place in step 1 and which type of oxides are removed in step 2?

Pieces of copper, iron, magnesium and zinc are added to separate test-tubes containing dilute hydrochloric acid.
Which test-tube contains iron and dilute hydrochloric acid?

Which processes are used in the treatment of water?

A factory burns coal with a high sulfur content.
Which pollutant is most likely to lead to the death of trees?

What is the correct order of abundance of the gases in the air?

The diagram shows an experiment to investigate how paint affects the rusting of iron.

What happens to the water level in tubes P and Q?

The diagram shows two substances, X and Y, being heated together.
The Universal Indicator paper turns blue during the experiment.
What are substances X and Y?

Carbon dioxide is produced when dilute hydrochloric acid reacts with

A student is asked to draw a diagram showing the uses of limestone.

Which numbered lines show a correct use of limestone?

Which structure is correctly named?

Which properties of the different compounds in petroleum enable its separation into fractions?
1. boiling point
2. chain length
3. chemical reactivity
4. solubility in water

Alkenes have the general formula $C_nH_{2n}$.
Which of the following is an alkene?

Bitumen is a substance obtained from the fractional distillation of petroleum. Which row describes its boiling point and the size of its molecules?
[Table_1]

A hydrocarbon X is cracked to make Y and hydrogen.
Compound Z is formed by the addition polymerisation of Y.
To which homologous series do X, Y and Z belong?
[Table_1]

Which row is correct for ethanol? [Table_1]