Chemistry Past Questions And Answers
Consider the reaction:
2A\(_{(g)}\) \(\Leftrightarrow\) B\(_{(g)}\) + C\(_{(g)}\) \(\Delta\)H = +25.6 kJ.
Which of the following changes will favour the formation of the products of the reaction represented above, at equilibrium?
- A) decrease in temperature
- B) increase in pressure
- C) increase in temperature
- D) decrease in volume
Which of the following pH values is likely to be that of a slightly alkaline system?
- A) 2
- B) 5
- C) 7
- D) 8
Unsaturated organic compounds are identified by decolourization of
- A. silver bromine and potassium tetraoxomanganate (VII) solutions
- B. bromine water and acidified potassium tetraoxomanganate (VII) solution
- C. silver bromide solution and bromine water
- D. bromine water and alkaline potassium tetraoxomanganate (VII) solution
Water has a rather high boiling point despite its low molecular mass because of the presence of?
- A. hydrogen bonding
- B. covalent bonding
- C. ionic bonding
- D. metallic bonding
The modern process of manufacturing steel for iron is by
- A. treatment with acids
- B. oxidation
- C. blast reduction
- D. treatment with alkanal
Citrus fruits such as lemon and grape taste sour because they contain
- A) ascorbic acid and citric acid
- B) citric acid and ascetic acid
- C) citric acid and dilute HCl
- D) citric acid and salicyclic acid
Which of the following are chemical changes? I. cooking of food II. digestion of food III. freezing of water IV. water is heated up
- A. I and II
- B. I, II, and III
- C. III and IV
- D. all of the above
2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g) From the equation above, calculate the mass of sodium hydroxide produced by 2.3g of sodium. [H = 1, O = 16, Na = 23]
- A. 0.40g
- B. 0.80g
- C. 4.00g
- D. 8.00g
2-methylprop-1-ene is an isomer of
- A) 3-methyl but-1-ene
- B) 2-methyl but-1-ene
- C) but-2-ene
- D) pent-2-ene
The functional group represented in the compound CH\(_3\)-CH\(_2\)-CH\(_2\)-CH\(_2\)-CH=O is
- A) Alkanone
- B) Alkanal
- C) Alkanol
- D) Alkanoate