Atomic Structure (CIE AS Chemistry)

The composition of atoms and ions can be determined from knowledge of atomic number, nucleon number and charge.

Complete Table 1.1.

Table 1.1 

Atomic number	Nucleon number	Number of electrons	Number of protons	Number of neutrons	Symbol
9		10
		23	26	32

Lithium and potassium are Group 1 metals. 

State the following for the potassium 1+ ion with a nucleon number of 39.

Symbol .......................................

Full electronic configuration .................................................

Beams of protons, neutrons and electrons behave differently in an electric field due to their differing properties.

Fig. 1.1 shows the path of a beam of electrons in an electric field.

Add and label lines to Fig. 1.1 to represent the paths of beams of protons and neutrons in the same field.

The fifth to eighth ionisation energies of three elements in the third period of the Periodic Table are given. The symbols used for reference are not the actual symbols of the elements.

The model of the nuclear atom was first proposed by Ernest Rutherford. He developed this model on the basis of results obtained from an experiment using gold metal foil.

Complete the Table 2.1 with information for two of the particles in an atom of ¹⁹⁷Au.

A sample of gold found in the earth consists of only one isotope.

Gold(III) chloride, traditionally called auric chloride, is one of the most common compounds of gold.

It has the formula AuCl₃.

Complete the electron configuration for the chloride ion using box notation.

On the axes shown in Fig. 2.1, draw a sketch diagram of one of each different type of orbital that is occupied by the electrons in a Period 3 element. 

Label each type of orbital. 

Fig. 2.1

All elements have a value for a first ionisation energy. 

Table 3.1 shows successive ionisation energies of an element A, found in period 3 of the Periodic Table.

Table 3.1

Identify element A. Explain your answer using data from Table 3.1.

Fig. 3.1 shows the trend in ionisation energy for Period 3 of the Periodic Table.

Fig. 3.1

Explain why the second ionisation energy of aluminium is a larger value than the first ionisation energy.

Iron and cobalt are adjacent elements in the Periodic Table. Iron has three main naturally occurring isotopes, cobalt has one.

Explain the meaning of the term isotope.

Isotopes of polonium, proton number 84, are produced by the radioactive decay of several elements including thorium, proton number 90. The isotope ²¹³Po is produced from the thorium isotope ²³²Th.

Complete Table 4.1 below to show the atomic structures of the isotopes ²¹³Po and ²³²Th.

Table 4.1 

Polonium has twenty five different isotopes.

Explain why the isotopes of polonium exhibit the same chemical reactions but their boiling points differ slightly.  

The first six ionisation energies of an element X are given below in Table 5.1.

Table 5.1

Write an equation, with state symbols, for the second ionisation energy of element X.

Use the data given above to deduce in which group of the Periodic Table element X is placed. Explain your answer.

Group ........................................................

Explanation ............................................................ 

The first ionisation energies (I.E.) for the elements of Group 4 are given below in Table 5.2.

Table 5.2

Explain the trend shown by these values in terms of the atomic structure of the elements.

Write the full electronic configuration for germanium.

Fig. 1.1 shows the elements from the first three periods of the Periodic Table.

Fig. 1.1

Identify an element that fits each of the following descriptions:

Fig. 1.2 shows the first ionisation energies for six consecutive elements labelled A-F. 

Fig. 1.2 

Complete the graph to show the first ionisation energies of elements G-K.

Explain why the value of the first ionisation energy for D is greater than for C.

Successive ionisation energies provide evidence for the arrangement of electrons in atoms. In Table 2.1, the successive ionisation energies of oxygen are given.

Table 2.1

Give the full electron configuration of the following atoms and ions.

Palladium is a transition metal that is primarily used in a catalytic converter.

Copper is an easily moulded base metal that is often added to precious metals to improve their elasticity, flexibility, hardness, colour, and resistance to corrosion.

Table 3.1 shows the number of protons, neutrons and electrons of different isotopes and ions of copper.

Calculate the percentage abundance of ⁶³Cu with a mass of 62.9296 and ⁶⁵Cu with a mass of 64.9278, when the average mass of the Cu isotope is 63.546.

Express your answer to an appropriate number of significant figures.

Explain why the isotopes of copper exhibit the same chemical reactions but their densities differ.

Copper can form a salt with chlorine to form copper(II) chloride. This reacts with sodium phosphate to form two different salts only.

Write a balanced equation for this reaction.

Table 4.1 below shows the atomic radii for the elements of Period 2, Li to F.

Table 4.1 

Complete Fig. 4.1 to show the electronic configuration of boron in the excited state.

Explain why the first ionisation energy of boron is lower than the first ionisation of beryllium.

The successive ionisation energies for another element, J, are shown in Table 4.2.

State the formula of the compound when element J reacts with chlorine. 

In the blast furnace, carbon can react with oxygen to form carbon dioxide and carbon monoxide.

Write one equation for the this reaction. 

Identify and draw the subshell on Fig. 5.1 which has the highest occupied energy level in an oxygen atom.

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