Explain — 4 marks
A student is learning about the periodic table and how elements are arranged. She notices that sodium (Na) is in Group 1 and has a melting point of 98°C, while chlorine (Cl) is in Group 17 and is a gas at room temperature. She wonders why elements in the same period behave so differently.
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Explain what the group number tells us about sodium (Na) in Group 1.
[1 mark]
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Explain why chlorine (Cl) is a gas at room temperature whilst sodium (Na) is a solid.
[2 marks]
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Explain how the periodic table is arranged and why sodium and chlorine are in different groups despite being in the same period.
[1 mark]
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State — 2 marks
A student is learning about the organisation of the periodic table and examining a periodic table poster in their classroom. They notice that elements are arranged in rows and columns with specific patterns.
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State what the vertical columns in the periodic table are called.
[1 mark]
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State the name of the horizontal rows in the periodic table.
[1 mark]
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Suggest — 5 marks
A student is investigating the properties of different elements. She collects samples of sodium, magnesium, aluminium, and silicon. She observes that sodium is soft and can be cut with a knife, while silicon is very hard and brittle. She wants to understand how the periodic table helps explain these differences.
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Suggest why sodium is a soft metal that can be cut with a knife, whilst silicon is hard and brittle.
[2 marks]
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The student predicts that potassium will be even softer than sodium. Suggest why the periodic table supports this prediction.
[2 marks]
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Suggest how the student could use the periodic table to predict the properties of magnesium, without carrying out any experiments.
[1 mark]
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Calculate — 2 marks
Sodium chloride is produced industrially by the evaporation of seawater or brine. It is used in food seasoning, water treatment, and as a raw material in the chemical industry. Sodium (Na) has atomic number 11 and mass number 23. Chlorine (Cl) has atomic number 17 and mass number 35.
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(01.1) Calculate the number of neutrons in an atom of sodium.
[1 mark]
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(01.2) A chloride ion has a charge of 1–. Calculate the number of electrons in a chloride ion.
[1 mark]
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State — 3 marks
A chemist is selecting halogens for use in industrial chemical synthesis. The chemist needs to consider the reactivity of different halogens when planning the reaction conditions.
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(01.1) State the trend in reactivity of the halogens going down Group 7.
[1 mark]
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(01.2) State two reasons why chlorine is more reactive than iodine.
[2 marks]
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- (01.1) Reactivity decreases down the group
- (01.2) Chlorine atoms are smaller (than iodine atoms)
- (01.2) The outer shell of chlorine is closer to the nucleus
- (01.2) Chlorine has fewer electron shells
- (01.2) The force of attraction between nucleus and electrons is stronger in chlorine
GCSE Perfect