2002 年

Which of the following equations represents a redox reaction ?

Ammonium dichromate, (NH₄)₂Cr₂O₇, decomposes on heating to give chromium(III) oxide, water and nitrogen. What mass of water is obtained when 126 g of ammonium dichromate undergoes complete decomposition ? (Relative atomic masses: H = 1.0, N = 14.0, O = 16.0, Cr = 52.0)

Gases X and Y react to give a gaseous product Z. The reaction can be represented by the equation: X(g) + 3Y(g) → 2Z(g) In an experiment, 40 cm³ of X and 60 cm³ of Y are mixed and are allowed to react in a closed vessel. What is the volume of the resultant gaseous mixture? (All volumes are measured at room temperature and pressure.)

Which of the following solution does NOT react with sodium hydroxide solution?

The symbol of vanadium is V. What is the oxidation number of vanadium in NH₄VO₃ ?

Which of the following acids, when heated with copper, would produce a gas ?

The monomer of polymer X is chloroethene. Which of the following statements concerning X is correct?

In a boiler using hard water, scale is deposited on its interior after a period of time. The scale consists mainly of metal carbonates. Which of the following substances can be used to remove the boiler scale ?

Which of the following gases contains the greatest number of molecules at room temperature and pressure ? (Relative atomic masses: H = 1.0, N = 14.0, O = 16.0, Cl = 35.5)

When a piece of copper is dropped into an aqueous solution of compound X, the copper gradually dissolves. X is probably