Electronic structure

This question is about atoms and ions.

The model of the atom has changed over time.

In an early model, scientists thought the atom was a tiny sphere that could not be divided.

Figure 1 represents this early model of the atom.

The discovery of a subatomic particle led to a change in the model in Figure 1.

Which was the first subatomic particle to be discovered?

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In a later model of the atom, most of the mass was concentrated in the centre of the atom.

What is the name of the centre of an atom?

Atoms contain three types of subatomic particle.

Draw one line from each subatomic particle to the relative charge of the particle.

What is meant by the ‘atomic number of an atom’?

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Table 1 shows information about two isotopes of an element.

Calculate the relative atomic mass (A_r) of the element.

Use the equation:

A = (mass number × percentage) of isotope A + (mass number × percentage) of isotope B

Give your answer to 1 decimal place.

An oxygen atom has eight electrons.

Complete Figure 2 to show the electronic structure of an oxygen atom.

Figure 2

Figure 3 represents two models of sodium chloride.

What are two advantages of model B compared with model A ?

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Potassium is in Group 1 of the periodic table.

What name is given to Group 1 elements?

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A potassium atom is very small.

What is the radius of a potassium atom?

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What name is given to the number of protons in an atom?

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Table 1 shows the name and the relative charge of the particles in a potassium atom.

Complete Table 1.

The electronic structure of a potassium atom is 2,8,8,1

Figure 1 represents the electronic structure of a potassium ion.

What is the charge on a potassium ion ?

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Figure 2 shows the melting points of some Group 1 elements.

Predict the melting point of potassium.

Potassium has two isotopes.

Table 2 shows the percentage (%) abundance of the two isotopes.

How is the relative atomic mass (A_r) of potassium calculated?

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This question is about the periodic table and argon.

What order did scientists use to arrange elements in early periodic tables? Tick (✓) one box.

In early periodic tables some elements were placed in the wrong groups. Mendeleev overcame some of these problems in his periodic table. Complete the sentence.

been discovered.

What is the name of the group that contains argon? Tick (✓) one box.

An atom of argon is represented as 40Ar 18 Determine the number of protons and the number of neutrons in one atom of argon.

39 38 Different atoms of argon are, Ar and Ar 18 18 What is the name given to these different atoms of argon?

Tick (✓) one box.

40 What is the electronic structure of an argon atom, Ar ? 18 Tick (✓) one box.

Why is argon unreactive?

This question is about sodium and chlorine. Figure 13 shows the positions of sodium and chlorine in the periodic table.

State one difference and one similarity in the electronic structure of sodium and of chlorine.

Sodium atoms react with chlorine atoms to produce sodium chloride (NaCl). Describe what happens when a sodium atom reacts with a chlorine atom. Write about electron transfer in your answer.

The reaction between sodium and chlorine is an exothermic reaction. Complete the reaction profile for the reaction between sodium and chlorine.

This question is about sodium and chlorine. Figure 2 shows the positions of sodium and chlorine in the periodic table.

State one difference and one similarity in the electronic structure of sodium and of chlorine.

Sodium atoms react with chlorine atoms to produce sodium chloride (NaCl). Describe what happens when a sodium atom reacts with a chlorine atom. Write about electron transfer in your answer.

The reaction between sodium and chlorine is an exothermic reaction. Complete the reaction profile for the reaction between sodium and chlorine.