GCSE Chemistry Paper 1 Higher Tier Practise Flashcards

A set of practice questions and answers covering salt production, the periodic table, atomic structure, electrolysis, and chemical energetics as described in the GCSE Chemistry Higher Tier Paper 1 transcript.

What are the three products formed when copper carbonate reacts with sulfuric acid?

Copper sulfate, water, and carbon dioxide.

What observation indicates that copper carbonate is in excess when added to sulfuric acid?

Unreacted copper carbonate powder remains at the bottom of the beaker or the solution stops fizzing.

Write the formula for calculating percentage yield based on the lecture transcript.

\text{% yield} = \frac{\text{mass of salt actually produced}}{\text{maximum theoretical mass of salt that could be produced}} \times 100

Why is copper not suitable for producing a salt by reacting it with sulfuric acid?

Copper is not reactive enough to react with dilute sulfuric acid.

Why is sodium not used to produce a salt by reacting it directly with sulfuric acid in a school laboratory?

The reaction is too reactive, explosive, or dangerous.

How do the electronic structures of sodium and potassium compare?

Similarity: Both have one electron in their outer energy level (shell). Difference: Potassium has more energy levels (shells) than sodium.

What are two observations made when potassium reacts with water?

1. Effervescence or fizzing. 2. The potassium melts into a ball and burns with a lilac flame.

What color does universal indicator turn when added to potassium hydroxide solution, and why?

The color turns purple or blue because the solution is alkaline.

Moving down Group 7 (the halogens), what are the trends for relative molecular mass and boiling point?

Both the relative molecular mass and the boiling point increase.

What is the definition of 'isotopes' in terms of subatomic particles?

Atoms of the same element with the same number of protons but a different number of neutrons.

Why does a polystyrene cup provide more accurate results than a glass beaker in thermochemical experiments?

Polystyrene is a better thermal insulator than glass, which reduces heat loss to the surroundings.

What is the ionic equation for the reaction between zinc and copper sulfate solution?

$$Zn(s) + Cu^{2+}(aq) \rightarrow Zn^{2+}(aq) + Cu(s)$$

Describe the electron transfer when calcium chloride ($CaCl_2$) is formed from calcium and chlorine atoms.

The calcium atom loses two electrons to form a $Ca^{2+}$ ion, and two chlorine atoms each gain one electron to form two $Cl^-$ ions.

Why is it impossible to electrolyse solid calcium chloride?

The ions are in a fixed lattice and are not free to move and carry a charge.

What product is formed at the negative electrode (cathode) during the electrolysis of aqueous calcium chloride?

Hydrogen gas (because calcium is more reactive than hydrogen).

What is the half equation for the reaction at the positive electrode (anode) during the electrolysis of aqueous calcium chloride?

$$2Cl^- \rightarrow Cl_2 + 2e^-$$

How does a metal like iron conduct thermal energy?

Energy is transferred by delocalised electrons that are free to move through the metallic structure.

Why are alloys harder than pure iron?

Alloys contain atoms of different sizes which disrupt the regular layers of the metal, making it harder for the layers to slide over each other.

What is the correct chemical equation for the reaction between 0.12 mol of iron and 0.18 mol of chlorine ($Cl_2$)?

$$2Fe + 3Cl_2 \rightarrow 2FeCl_3$$

Why does propane ($C_3H_8$) have a low boiling point?

Propane has weak intermolecular forces that require very little energy to overcome.

What is meant by the term 'weak acid'?

An acid that is only partially ionised or dissociated in aqueous solution.

What happens to the pH of an acid as it is diluted with water?

The concentration of $H^+$ ions decreases, causing the pH to increase toward $7$.

Explain why calcium is more reactive than magnesium.

Calcium atoms are larger than magnesium atoms, meaning the outer electrons are further from the nucleus and more shielded, so they are less strongly attracted and more easily lost.