Inorganic Chemistry

Describe how the student could use a chemical test to show whether the liquid contains water, and explain what her result would mean about the presence of water.

The student measures the boiling point of the liquid and finds it to be 102°C (at 1 atmosphere pressure). Calculate the difference between this boiling point and the boiling point of pure water under these conditions, and explain what this result shows about the purity of the liquid.

To test for dissolved chloride ions, the student adds dilute nitric acid, followed by silver nitrate solution. She obtains a white precipitate. Explain why it is important to add the nitric acid before the silver nitrate solution in this test.

State the name of the gas given off by X when warmed with sodium hydroxide, and describe how you would test for it (including the result expected).

Solution Y gives a yellow precipitate when tested with silver nitrate and dilute nitric acid. State which ion is present in Y, and the name and colour of the precipitate formed.

Describe how you could distinguish between the precipitates formed with chloride and iodide ions using this test.

Describe a test to identify which solid, X or Y, contains the carbonate ion. Calculate the minimum volume of 1.0 mol/dm³ hydrochloric acid required to completely react with 0.05 mol of carbonate present in one of the solids. Show your working.

Solid Y is warmed with sodium hydroxide solution. Ammonia gas is produced.

Describe the test and give a calculation to show how many moles of ammonium ions would be present if 672 cm³ of ammonia gas is collected at room temperature and pressure. (1 mol of gas occupies 24,000 cm³ at r.t.p.)

Describe how the student could test solution A to check if it is pure water. Explain the result that would show if it is not pure.

The student adds a white powder to solution B and observes effervescence. The gas produced is bubbled through limewater which turns cloudy.

Explain what ions are present in the white powder and write the ionic equation for the reaction.

The student wishes to know if any ammonium ions are present in the white powder. Describe a test for ammonium ions and explain how the result confirms their presence.

Describe the chemical test used to show if the powder contains water.

A sample of the powder is added to dilute acid and gas is released. The gas is bubbled through limewater, which becomes cloudy.

Describe how copper metal can be used to determine the percentage of oxygen in air, including the main observations and calculation.

Explain why copper must be in excess in this experiment.

Define what is meant by 'oxidising agent' and 'reducing agent' in a chemical reaction.

State which substance is the oxidising agent when magnesium reacts with copper(II) oxide, and briefly justify your answer.

A student combusts magnesium in pure oxygen and collects 4.8 g of magnesium oxide as product. Write a balanced equation for this reaction.

Calculate the minimum mass of magnesium that could have reacted to produce 4.8 g of magnesium oxide (MgO). [Mg = 24, O = 16]

If the products from part (a) are mixed with copper(II) oxide and heated, a reaction occurs. Write an equation for the displacement reaction.

State which metal is reduced in this reaction, and explain your answer.

Calculate the maximum mass of copper that can be formed if 4.8 g of MgO (from part (a)) originally came from enough Mg, and all the Mg is used to displace copper from CuO. [Cu = 64]

State whether the oxide formed when sulfur burns in oxygen is acidic or basic, and give a reason.

When magnesium burns in oxygen, what type of oxide is formed? How does it behave in water?

For the reaction: Zn(s) + CuO(s) → ZnO(s) + Cu(s) Explain in terms of oxygen transfer which substance is oxidised and which is reduced.

Give the definition of oxidation in terms of electron transfer, and state which substance is oxidised in the reaction in (c).

State what is meant by a 'greenhouse gas' and name one greenhouse gas present in the Earth’s atmosphere.

Explain how carbon dioxide is released into the atmosphere during the combustion of fossil fuels.

Describe one possible environmental impact caused by an increase in greenhouse gases such as carbon dioxide.

In the following reaction, identify the oxidising agent and explain your answer in terms of oxygen transfer: Mg(s) + CuO(s) → MgO(s) + Cu(s)

Suggest why carbon dioxide is not removed from the atmosphere as quickly as it is added by combustion.

Write the word equation and the balanced symbol equation for the thermal decomposition of copper(II) carbonate.

State the products formed when copper(II) carbonate is heated.

Explain, in terms of electron transfer, which substance is reduced in the extraction of copper from copper(II) oxide using carbon.

Write the half-equation for the reduction of copper(II) ions to copper atoms.

Identify the reducing agent in the reaction between copper(II) oxide and carbon and explain your answer.