C9 - The Periodic Table

Question 1

How are elements ordered in the periodic table? [1]

Answer 1

• By increasing atomic number (number of protons)

Question 2

What are vertical columns in the periodic table called? [1]

Answer 2

• Groups

Question 3

What are horizontal rows in the periodic table called? [1]

Answer 3

• Periods

Question 4

What is the trend in metallic character across a period? [1]

Answer 4

• A gradual change from metal to no-metal

Question 5

What happens to the number of electrons in the outer shell of an element across a period? [1]

Answer 5

• It increases

Question 6

What happens to the structure of an element across a period? [1]

Answer 6

• Giant metallic (e.g. Li) - giant covalent (e.g. C) - simple molecular (e.g. Ne)

Question 7

Why do elements in the same group react in a similar way? [1]

Answer 7

• They have the same number of electrons in the outer shell.

Question 8

What is the same for elements in the same period? [1]

Answer 8

• They have the same number of shells of electrons

Question 9

What are the properties of group 1 elements (the alkali metals)? [2]

Answer 9

• They are good conductors of heat and electricity
• They are soft metals

Question 10

What are the trends in group 1 as you go down the group? [3]

Answer 10

• Reactivity increases
• Density increases
• Melting point decreases

Question 11

Write the balanced symbol equation for the reaction of lithium with oxygen [1]

Answer 11

• 4Li (s) + O₂ (g) → 2Li₂O (s)

Question 12

Write the balanced symbol equation for the reaction of sodium with water [1]

Answer 12

• 2Na (s) + 2H₂O (l) → 2NaOH (aq) + H₂ (g)

Question 13

Write the balanced symbol equation for the reaction of rubidium with chlorine [1]

Answer 13

• 2Rb (s) + Cl₂ (g) → 2RbCl (s)

Question 14

Describe the appearance of the halogens chlorine, bromine and iodine [3]

Answer 14

• Chlorine is a pale yellow-green gas
• Bromine is a red-brown liquid
• Iodine is a grey-black solid

Question 15

The halogens are diatomic, describe what this means [1]

Answer 15

• There are two atoms in the molecule (e.g Cl₂)

Question 16

What are the trends in group 7 as you go down the group? [3]

Answer 16

• Reactivity decreases
• Melting point increases
• They become darker

Question 17

Write the balanced symbol equation for the reaction of chlorine and hydrogen [1]

Answer 17

• H₂ (g) + Cl₂ (g) → 2HCl (g)

Question 18

Write the balanced symbol equation for the reaction of chlorine with iron (III) [1]

Answer 18

• 2Fe (s) + 3Cl₂ (g) → 2FeCl₃ (s)

Question 19

Describe what happens in a displacement reaction [1]

Answer 19

• A more reactive element displaces a less reactive element from a compound

Question 20

Write the balanced symbol equation for the displacement reaction between potassium iodide and chlorine [1]

Answer 20

• 2KI (aq) + Cl₂ → 2KCl (aq) + I₂ (aq)

Question 21

Write the balanced symbol equation for the displacement reaction between potassium iodide and chlorine [1]

Answer 21

• 2KI (aq) + Cl₂ → 2KCl (aq) + I₂ (aq)

Question 22

Describe the properties of transition metals [5]

Answer 22

• High density
• High melting point
• Good conductors
• Form coloured compounds
• Can act as catalysts

Question 23

Describe the noble gases (group 8/0) [1]

Answer 23

• Unreactive monoatomic gases

Question 24

Explain why the noble gases are unreactive? [1]

Answer 24

• They have a full outer shell of electrons

Question 25

Describe the uses of halogens [2]

Answer 25

• Argon in lamps
• Helium in balloons