Chemistry Past Questions And Answers
1311
Which of these has the lowest pH value?
- A) calcium trioxocarbonate (IV)
- B) sodium trioxocarbonate (IV)
- C) hydrochloric acid
- D) hydrocarbon acid
1312
A constituent common to bronze and solder is
- A) lead
- B) silver
- C) copper
- D) tin
1313
The best indicator to use for the titration of ethanoic acid with sodium hydroxide is
- A. methyl orange
- B. phenolphthalein
- C. screened methyl orange
- D. methyl red
1314
A subtance is said to be hygroscopic if it absorbs
- A. water from the atmosphere to form a solution
- B. heat from the surrounding
- C. carbon (IV) oxide from the atmosphere
- D. moisture from the atmosphere without dissolving
1315
Which of the following oxides can be reduced by hydrogen?
- A. Aluminium oxide
- B. Magnesium oxide
- C. Sodium oxide
- D. Silver oxide
1316
The alkali metals exhibit similar chemical properties because
- A. they occur in the combined state
- B. they have the same number of vallence electrons
- C. they form crystalline salts
- D. their salts are soluble in water
1317
Which of the following combination of reagents will react to give chlorine gas?
- A) Sodium chloride, conc. H2SO4 ?and Manganese (IV) oxide
- B) Potassium tetraoxomangate (vii) and conc. H2SO4
- C) Potassium trioxochlorate (v) and conc. H2SO4
- D) Potassium tetraoxomangate (Vl) and conc H2SO4
1318
The Avogadro number of 24g of magnesium is the same as that of
- A. 1g of hydrogen molecules
- B. 16g of oxygen molecules
- C. 32g of oxygen molecules
- D. 35.5g of chlorine molecules
1319
An element with atomic number twelve is likely to be
- A) electrovalent with a valency of 1
- B) electrovalent with a valency of 2
- C) covalent with a valency 2
- D) covalent with a valency of 4
1320
Which of the following pairs has compounds that are isomers?
- A. Propanal and propanone
- B. Ethanoic acid and ethylmethanoate
- C. Ethanoic acid and ethane-1, 2-diol
- D. 2-methylbutane and 2, 2-dimethylbutane