GCSE Combined Science Atoms & periodic table questions by topic

Sort each substance into element, compound or mixture.

1. (a)Classify: oxygen gas; sodium chloride; air; copper.[4]

Choose a separation method for each mixture.

1. (a)Sand mixed with water.[1]
2. (b)Sugar dissolved in water, where you want the sugar back.[1]
3. (c)Ethanol and water (miscible liquids with different boiling points).[1]
4. (d)Two dyes in a food colouring.[1]

An atom of aluminium has atomic number 13 and mass number 27.

1. (a)State the numbers of protons, neutrons and electrons in this atom.[3]
2. (b)Name the particle with no charge.[1]

Write the electronic structures of these atoms.

1. (a)Carbon (atomic number 6).[1]
2. (b)Neon (atomic number 10).[1]
3. (c)Magnesium (atomic number 12).[1]
4. (d)State the group of magnesium from its structure.[1]

Boron exists as two isotopes: boron-10 (20% abundance) and boron-11 (80% abundance).

1. (a)Explain what makes these atoms isotopes of each other.[2]
2. (b)Calculate the relative atomic mass of boron.[2]

Order the story of the atomic model.

1. (a)Arrange these models in date order: nuclear atom, shells, plum pudding, indivisible sphere.[2]
2. (b)State the experimental result that disproved the plum pudding model.[2]

A student drops small pieces of lithium and potassium into separate troughs of water.

1. (a)Give the word equation for the lithium reaction.[2]
2. (b)Describe how the potassium reaction differs in violence, and explain why.[3]

Chlorine water is added to a solution of potassium bromide.

1. (a)State and explain what you would observe.[2]
2. (b)Predict, with a reason, what happens when iodine solution is mixed with potassium chloride solution.[2]

Explain why Mendeleev’s periodic table was accepted while earlier attempts were not.

1. (a)Describe two features of Mendeleev’s table.[2]
2. (b)Explain how his predictions strengthened the case for it.[2]
3. (c)State one change made in the modern table and why it fixed remaining problems.[2]

Explain the trends in Group 7.

1. (a)Describe the trend in boiling points down the group and explain it.[2]
2. (b)Describe the reactivity trend and explain it in terms of electron shells.[3]

Silver has two isotopes: silver-107 (52% abundance) and silver-109 (48% abundance).

1. (a)Silver’s atomic number is 47. State the numbers of neutrons in each isotope.[2]
2. (b)Calculate the relative atomic mass of silver.[2]
3. (c)Explain why the answer is not a whole number.[1]

Argon is used to fill light bulbs and to shield welds.

1. (a)Explain, in terms of electrons, why argon is suitable for these uses.[2]
2. (b)Describe the trend in boiling points down Group 0 and link it to a use of the heaviest noble gases.[2]