Chapter 17 Elements and Their Properties

Reactivity of halogen decreases going down the group because

• The 8th electron difficult to attract by nucleus

• Atomic size decreases down the group

• Electrons are closer to the nucleus

• Screening effect decreases

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Which of the following is a solid at room temperature?

• Fluorine

• Chlorine

• Bromine

• Iodine

Which of the following properties decreases going down the group?

• Boiling point

• Reactivity

• Melting point

• Atomic radius

How is the appearance of bromine?

• purple solid

• brown liquid

• green gas

• yellow gas

Element X dissolves in water to produce a solution that turns the blue litmus paper red and then decolourised. What is element X?

• Sodium

• Bromine

• Sulphur

• Neon

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Two chemical properties of element W are shown above.

Based on the information given which of the following is another property of element W?

• W reacts with water to liberate hydrogen gas

• W is very electropositive

• W reacts with sodium hydroxide solution to form salts with the formulae NaW and NaOW

• W is a good electrical conductor

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Element G, L and J are located in Group 17 of the Periodic Table. Element J is more electronegative than element G. The reaction of red-hot iron wool with gas L is more vigorous than the reaction of red-hot iron wool with gas J. The reactivity of these three elements in ascending order is ?

• G, J, L

• L, J, G

• L, G, J

• J, G, L

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Table shows the electron arrangement of atoms X and atom Y. Which of the following statements is true about element X and Y?

• Element Y is more electronegative than element X

• Both the elements, X and Y, are good electrical conductors

• An atom of X can accept an electron more readily than an atom of Y

• An aqueous solution of element X is acidic but an aqueous solution of element Y is alkaline

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Element R forms an ion, R^- with an electron arrangement of 2.8.8. The chemical properties of element R are similar to another element with a proton number of?

• 9

• 12

• 16

• 19

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Based on what you have learnt, predict the properties of Astatine. Given that Astatine is an element in Group 17 of the Periodic Table.

• Dark brown colour gas with a rapid reaction with H₂O to give 2 acids

• Black colour solid with a no reaction with H₂O

• Black colour solid with a very slow reaction with H₂O to give 2 acids

• Dark brown colour solid with a no reaction with H₂O

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