Properties of small molecules

Table 8 shows diagrams which represent the structures of two substances.

Compare the structure and bonding of sodium chloride and oxygen.

Table 2 shows diagrams which represent the structures of two substances.

Compare the structure and bonding of sodium chloride and oxygen.

This question is about structure and properties.

Which pair of substances both contain atoms in hexagonal rings? Tick (✓) one box.

Explain why the structure of copper allows the conduction of thermal energy.

Explain why copper oxide (CuO) has a high melting point.

Explain why water (H₂O) has a low melting point.

This question is about structure and bonding.

Figure 5 represents part of a carbon molecule.

Name the type of carbon molecule in Figure 5.

Suggest one property that makes the carbon molecule in Figure 5 useful in nanotechnology.

An alloy of aluminium contains small amounts of other metals. Explain why other metals are added to aluminium.

Figure 6 represents part of the structure of a polymer.

Compare the bonding within the chains with the forces between the chains in this polymer.

This question is about substances with covalent bonding.

Figure 12 shows a ball and stick model of a water molecule (H₂O).

Suggest one limitation of using a ball and stick model for a water molecule.

Ice has a low melting point. Water molecules in ice are held together by intermolecular forces. Complete the sentence. Ice has a low melting point because the intermolecular forces are.

Figure 13 shows the structure of a molecule.

What is the molecular formula of the molecule in Figure 13 ?

Diamond has a giant covalent structure.

What is the number of bonds formed by each carbon atom in diamond? Tick (✓) one box.

Give two physical properties of diamond.

Name two other substances with giant covalent structures.

This question is about substances with covalent bonding.

Figure 2 shows a ball and stick model of a water molecule (H₂O).

Suggest one limitation of using a ball and stick model for a water molecule.

Ice has a low melting point. Water molecules in ice are held together by intermolecular forces. Complete the sentence. Ice has a low melting point because the intermolecular forces are.

Figure 3 shows the structure of a molecule.

What is the molecular formula of the molecule in Figure 3 ?

Diamond has a giant covalent structure.

What is the number of bonds formed by each carbon atom in diamond? Tick (✓) one box.

Give two physical properties of diamond.

Name two other substances with giant covalent structures.

This question is about oxygen and compounds of oxygen.

What is the state symbol of oxygen at room temperature?

Figure 4 shows the percentage by mass of the elements calcium, carbon and oxygen in calcium carbonate.

What is the percentage by mass of calcium in calcium carbonate?

At high temperature, sodium nitrate decomposes into sodium nitrite and oxygen. A student heats three samples of sodium nitrate. The mass of each sample was 4.50 g The mass of solid after heating was recorded. Table 2 shows the mass of solid after heating in each experiment.

Calculate the mean mass of solid after heating. Give your answer to 3 significant figures.

Table 3 shows the electronic structure of hydrogen and oxygen.

Figure 5 shows part of a dot and cross diagram of a molecule of water (H₂O). Complete the dot and cross diagram. You should show only the electrons in the outer energy levels.

Oxygen and sulfur are examples of simple molecules.

Complete the sentence. Choose the answer from the box.

Figure 6 shows the relative sizes of an oxygen molecule and a sulfur molecule.

How does the boiling point of sulfur compare with the boiling point of oxygen? Complete the sentences.

than the intermolecular forces in oxygen.

This question is about elements in the periodic table.

What order did scientists use to arrange elements in early periodic tables?

In the early periodic tables some elements were placed in the wrong groups. Mendeleev overcame this in his periodic table. Give one way Mendeleev did this.

Table 2 shows the boiling points of fluorine, chlorine and bromine.

Explain why the boiling points in Table 2 are low.

Explain the trend in the boiling points in Table 2.

Explain why neon is unreactive. Give the electronic structure of neon in your answer.

How many atoms are there in 1 g of argon? The Avogadro constant is 6.02 × 10²³ per mole. Relative atomic mass (A_r): Ar = 40

This question is about sodium.

Sodium reacts with chlorine. What is the balanced equation for the reaction?

Tick (✓) one box.

Hot sodium is put in a gas jar of chlorine. Describe the observations made before, during and after the reaction.

Explain why sodium is less reactive than potassium.

Chlorine reacts with sodium and with hydrogen. Compare the structure and bonding in sodium chloride and hydrogen chloride.