2004 年

Which of the following combinations concerning the uses of metals is correct ?

Chlorine can be prepared from concentrated hydrochloric acid and potassium permanganate according to the following equation: 2KMnO₄ + xHCl → 2KCl + 2MnCl₂ + yH₂O + zCl₂ What is the value of z ?

The structure of polymer X can be represented by

What is the monomer of X?

Magnesium can be obtained from magnesium oxide by

The following paragraph was extracted from the laboratory report of a student on the preparation of an organic compound. CH₃CH₂CO₂H and CH₃CH₂OH were heated with a small amount of concentrated H₂SO₄ in a test tube for a few minutes. The resultant mixture was then added to a beaker of cold water. Which of the following statements concerning the experiment is correct ?

Which of the following reagents can be used to distinguish sodium bromide solution from sodium chloride solution ?

Which of the following concerning aqueous ammonia is correct?

A gaseous mixture consists of methane and ethane in a mole ratio of 1:1. It has a volume of 200 cm³ at room temperature and pressure. What is the volume of oxygen required, measured at room temperature and pressure, for the complete combustion of the mixture?

The main chemical constituent of bleaching power is calcium hypochlorite. Which of the following statements concerning bleaching power is INCORRECT ?

Element X has three isotopes, ²⁰⁶X, ²⁰⁷X and ²⁰⁸X. The graph below shows the relative abundances of the isotopes.

What is the relative atomic mass of X ?