An orange drink concentrate is suspected to contain traces of poisonous green dye and a harmless dye having the same boiling point. Which of the following techniques is most suitable for isolating the dyes?
- A. Fractional distillation
- B. Paper chromatography
- C. Coagulation
- D. Recrystallization
Which of the following factors that affect the rate of chemical reactions can be explained in terms of the collision theory? l. concentration ll. pressure lll. temperature lV catalyst
- A. l and ll only
- B. l, ll and lll only
- C. l and lll only
- D. l, II, lll and IV only
WHICH OF THE FOLLOWING SALTS IS READILY SOLUBLE IN WATER?
- A. PbCI2
- B. Pb(NO 3) 2
- C. PbSO4
- D. PbCO 3
What of the following pairs of acid and base will produce a solution with pH less than 7 at equivalence point?
- A. HNO3 and NaOH
- B. H2SO4 and KOH
- C. HCI and Mg(OH) 2
- D. HNO 3 and KOH
The reaction that takes place at the cathode when an aqueous solution of NaCI is electrolysed using carbon electrodes is
- A. 2H+2(g) + 2e- → H2(g)
- B. Na+2(g) + e- → Na(s)
- C. 4OH- → 2H2O(l) + O2(g) +4e-
- D. 2CI- → CI2(g) + 2e-
Which of the following compounds is a soapless detergent?
- A. C 12H 25OSO3Na
- B. C 17H 35COONa
- C. C 6H5OH3
- D. C 4H9COOC2H 5
The mass of 800cm3 of a gas X at s.t.p. is 1.0g. What is the molar mass of X? [1 mole of a gas at s.t.p occupies 22.4dm 3]
- A. 18.0g mol-1
- B. 22.4g mol-1
- C. 28.0gmol-1
- D. 36.0gmol-1
What is the IUPAC name of CH3CH2COOCH 3?
- A. Ethylethanoate
- B. Methylethanoate
- C. Methylpropanoate
- D. Propylmethanoate
Glucose gives a brick-red precipitate with Fehling’s solution because it is
- A. carbohydrate
- B. an alkanoate
- C. a reducing sugar
- D. a non-electrolyte
A solution of zinc chloride should not be stored in a container made of
- A. tin
- B. copper
- C. aluminium
- D. lead
Two solutions containing Pb2+ and AI3+ respectively can be distingusihed using
- A. NaOH(aq)
- B. NH3(aq)
- C. conc. HCI3
- D. conc. HCI
What quantity of electrons in moles is needed to discharge two moles of aluminum from aluminum oxide (AI 2O3)
- A. 1
- B. 2
- C. 4
- D. 6
Which of the following subtances will not produce effervescence with dilute hydeochloric acid?
- A. Copper (ll) trioxocarbonate (IV)
- B. Potassium hydrogentrioxocarbonate (lV)
- C. Zinc granules
- D. Sodium chloride
What are the values of x, y and z respectively in the following in the following equation? \(MnO_{2(s)} + xHCI_{(aq)} → MnCI_{2(g)} + yHO_{(l)} + zCI_{2(g)}\)
- A. 4,1,2
- B. 1,2,1
- C. 2,1,2
- D. 4,2,1
What volume of hydrogen would be left over when 300cm3 of oxygen and 1000cm of hydrogen are exploded in a sealed tube? [2H2(g) + O2(g) → 2H2 Og]
- A. 200 cm3
- B. 400 cm3
- C. 600cm3
- D. 700cm3
Which of the following salts is not prepared by precipitation?
- A. Lead (ll) trioxocarbonate (lV)
- B. Barium trioxocarbonate (IV)
- C. Sodium trioxocarbnate (IV)
- D. Calcium trioxocarbonate (IV)
The alloy used extensively in the building industry is
- A. steel
- B. bronze
- C. duralumin
- D. type metal
Which of the following pairs of salts undergo hydrolysis?
- A. AlCI3 and NH4CI
- B. AICI3 and NaCI
- C. FeCI3 and KCI
- D. Na2SO4 and K2 SO4
The method of collection of gases prepared in the laboratory depend on their
- A. odour and atomicity
- B. colour and odour
- C. atomicity and density
- D. solubility and density
Which of the following equipment is not used to detect radioactivity?
- A. Wilson cloud chamber
- B. Geiger- muller counter
- C. Mass spectrometer
- D. Photographic plate
A metal X forms two chlorides with the formulae XCI2 and XCI3. Where is X in the Periodic Table?
What type of bonding exists between X and chlorine in each of the chlorides?
- A. metallic bonding
- B. ionic bonding
- C. covalent bonding
- D. dative bonding