Chemistry JAMB, WAEC, NECO AND NABTEB Official Past Questions

2164

Which of the following compounds absorbs moisture from the atmosphere and dissolves in it?

  • A. FeCI3
  • B. MgSO4.7H2O
  • C. Na2SO 4
  • D. KCI
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2165

When aqueous ammonia is added to one of the following solutions,a white precipitate which dissolved in excess ammonia is formed Identify the solution.

  • A. ZnCl2(aq)
  • B. Pb(NO3)2(aq)
  • C. CuSO4(aq)
  • D. FeSO4(aq)
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2166

The indicator used in neutralizing CH3COOH and NaOH solution has pH range of

  • A. 3-5
  • B. 7-8
  • C. 8-103
  • D. 10-12
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2167

Which of the following aqueous methods cannot be used to distinguish between a strong acid and a a weak acid?

  • A. Conductivity measurement
  • B. Measurement of pH
  • C. Measurement of heat of neutralization
  • D. Action on starch iodide paper
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2168

Which of the following processes is an endothermic reaction?

  • A. Dissolving NH4CI crystals in water
  • B. Addition of concentrated H2SO4
  • C. Dissolving NaOH pellets in water
  • D. Passing SO3 gas into water
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2169

Considered the reaction: H+(aq) + OH (aq) → H2O
(l). The energy change taking place in the reaction above is enthalpy of

  • A. formation
  • B. hydration
  • C. neutralization
  • D. solution
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2170

Consider the reaction represented by the equation. 2NaHCO3(s) \(\rightarrow\) 2Na2CO 3(S) + CO 2(g) + H2O(g) what volume of carbon (IV)oxide at s.t.p is evolved when 0. 5 moles of NaHCO3 is heated? [Molar volume = 22.4 dm3 at s.t. p]

  • A. 1.12dm3
  • B. 2.24dm3
  • C. 5.6dm3
  • D. 56.0dm3
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2171

If 20 cm3 of distilled water is added to 80cm 3 of 0. 50 mol dm-3 hydrochloric acid, the new concentration of the acid will be

  • A. 0.10mol dm-3
  • B. 0.20mol dm-3
  • C. 0.40mol dm-3
  • D. 2.00mol dm-3
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2172

If 1 mole of sodium contains 6 x 1023 atoms, how many atoms are contained in 0.6 g of sodium? [Na = 23]

  • A. 1.56 x 1023
  • B. 1.56 x 1022
  • C. 3.6 x 1023
  • D. 3.6 x 1022
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2173

An atom 23892X decays by alpha particle emission to give an atom Y. The atomic number and mass number of Y are

  • A. 90 and 234 respectively
  • B. 91 and 238 respectively
  • C. 92 and 236 respectively
  • D. 93 and 238 respectively
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2174

An element X has isotopic masses of 6 and 7. if the relative abundance is 1 to 12.5 respectively, what is the relative atomic mass of X?

  • A. 6.0
  • B. 6.1
  • C. 6.9
  • D. 7.0
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2175

How many orbitals are in the d-sub shell?

  • A. 1
  • B. 3
  • C. 5
  • D. 7
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2176

In which of the following processes is biotechnology not applied?

  • A. Manufacture of drugs
  • B. Treatment of domestic sewage
  • C. Production of alcoholic beverages
  • D. Electroplating of metals
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2177

Which of the following substance is an alloy of lead?

  • A. Brass
  • B. Duralumin
  • C. Stainless steel
  • D. Soft solder
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2178

Which of the following pairs of solutions will produce a precipitate when mixed?

  • A. Pb(NO3)2(aq) and NaCI(aq)
  • B. MgSO4(aq) and HCI(aq)
  • C. ZnCI2(aq) and NaSO4(aq)
  • D. NaOH(aq) and HNO3(aq)
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2179

Hardness in water can be removed by adding

  • A. copper (ll) tetraoxosulphate (IV)
  • B. sodium trioxocarbonate (IV)
  • C. sodium chloride
  • D. alum
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2180

Ethyne undergoes the following reactions except

  • A. polymerisation
  • B. addition
  • C. substitution
  • D. esterification
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2181

Fats are classified as

  • A. hydrocarbons
  • B. alkanoates
  • C. alkanols
  • D. carbohydrates
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2182

The colour of the solution formed when ethyne reacts with an acidic solution of potassium tetraoxomanganate (VII) is

  • A. purple
  • B. colourless
  • C. green
  • D. pink
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2183

Which of the following substances is a non-reducing sugar?

  • A. Sucrose
  • B. Glucose
  • C. Fructose
  • D. Maltose
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2184

What is the major product formed when C2H5OH reacts with CH3COOH?

  • A. C2H5COOCH3
  • B. C2HCOCH3
  • C. CH3COOC2H5
  • D. C3H7COOH
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