Transition Elements (Cambridge O Level Chemistry)

The diagram shows part of the structures of sodium bromide and sulfur.

Describe both sodium bromide and sulfur in terms of:

bonding

electrical conductivity

solubility in water

Sulfur is an element.

What is meant by the term element?

A coloured crystal of cobalt(II) chloride is placed at the bottom of a beaker containing water.
Colour spreads throughout the water over time. Figure 1 shows the spread of colour after two days.

Figure 1

Cobalt is a transition element. Lithium is a Group I element.

Describe two ways in which the properties of cobalt differ from those of lithium.

Scandium, proton number 21, is not a typical transition element.

Scandium is a low density metal which has only one oxidation state in its compounds. Scandium compounds are white solids which form colourless solutions. Titanium, the next metal in the period, is a far more typical transition element. 

How would the properties of titanium differ from those of scandium?

Scandium fluoride is an ionic compound. The valency of scandium in scandium fluoride is three.

Draw a diagram which shows the formula of this compound, the charges on the ions and the arrangement of the valency electrons around the negative ions.

Use × to represent an electron from a fluorine atom.
Use ○ to represent an electron from a scandium atom.

Scandium oxide is insoluble in water. Describe how you could show that it is an amphoteric oxide.

This question is concerned with the elements in Period 5, Rb to Xe.

The electron distributions of some of these elements are given in the following list.

[1]

[1]

[1]

Predict two differences in physical properties and two differences in chemical properties between rubidium and the transition metal niobium.