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43

The most suitable indicator for the reaction between NaOH and HCOOH is?

  • A. bromocresol
  • B. methyl orange
  • C. methyl red
  • D. phenolphthalein
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44

A sample of air was bubbled into water. The PH of the water slowly changed from 7 to 6. Which of the following gases in the samples caused the change?

  • A. carbon(iv)oxide
  • B. carbon(ii)oxide
  • C. nitrogen
  • D. oxygen
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45

which of the following solutions containing one mole per dm\(^3\) of the compound would have the lowest PH?

  • A. ethanoic acid
  • B. hydrochloric acid
  • C. sodium chloride
  • D. sodium hydrogentrioxocarbonate(iv)
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46

Vinegar is an aqueous solution of?

  • A. Hydrochloric acid
  • B. ethanedioc acid
  • C. ethanoic acid
  • D. hydrofluoric acid
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47

What is the solubility of a salt X at 25ΒΊC if the saturated solution of the salt contains 0.28g in 100cm\(^3\) of the solution in mol\dm\(^3\)? 

[ X = 56.0g ]

  • A. 0.05
  • B. 0.10
  • C. 2.60
  • D. 2.80
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48

The properties of a good primary standard solution include the following except?

  • A. High molecular mass
  • B. low molecular mass
  • C. high degree of purity
  • D. readily available
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49

The name of the compound CH\(_3\)C(CH\(_3\))\(_2\)CH\(_2\)CH\(_2\)CH\(_3\)

  • A. 2 - methyl butane
  • B. 2,2 - dimethyl butane
  • C. 2 - methyl pentane
  • D. 2,2 - dimethyl pentane
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50

Which of the following compounds has coordinate bonds in its structure?

  • A. Al\(_2\)Cl\(_6\)
  • B. MgCl\(_2\)
  • C. AgCl
  • D. NaCl
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51

What is the percentage by mass of H in  CH\(_3\)COOH ?

  • A. 1.7%
  • B. 5.0%
  • C. 6.7%
  • D. 7.1%
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52

Stoichiometry is based on the law?

  • A. multiple proportion
  • B. constant composition
  • C. conservation of energy
  • D. conservation of mass
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53

How many moles of carbon(iv)oxide contains 16.0g of oxygen?

[ C = 12.0, O = 16.0 ]

  • A. 0.20 mol
  • B. 0.25 mol
  • C. 0.40 mol
  • D. 0.50 mol
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54

When an equilibrium is established between dissolved and undissolved solutes, the solution is said to be?

  • A. Saturated
  • B. Unsaturated
  • C. Concentrated
  • D. Diluted
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55

Which of the following pairs of components have the same molecular mass?

[ H = 1.0, C = 12.0, O = 16.0 ]

  • A. Ethene and Ethyne
  • B. Ethane and Ethene
  • C. Carbon (ii) Oxide and Ethene
  • D. Carbon (iv) Oxide and Ethyne
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56

Which of the substances is non-polar?

  • A. Bromine
  • B. Ammonia
  • C. Water
  • D. Hydrogen Bromide
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57

Calcium and magnesium belong to the group of the periodic table because both?

  • A. are metals
  • B. form cations
  • C. form colourless salts
  • D. have same number of valence electrons
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58

If 6.5g of magnesium ribbon reacts completely with Hydrochloric acid, how many grams of hydrogen gas would be liberated?

Mg(s) + 2 HCl(aq) –> MgCl 2(aq) + H 2(g)

[ H = 1.0, Mg = 24.0 ]

  • A. 0.54g
  • B. 0.70g
  • C. 1.08g
  • D. 1.40g
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59

The bleaching action of chlorine is through the process?

  • A. Hydration
  • B. Hydrolysis
  • C. Reduction
  • D. Oxidation
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60

which of the following elements has the highest ionization energy?

  • A. Calcium
  • B. Chlorine
  • C. Flourine
  • D. Magnesium
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61

Which of the following metals reacts slowly with cold water?

  • A. Iron
  • B. Silver
  • C. Calcium
  • D. Pottassium
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62

A solid with higher melting and boiling points is likely to be?

  • A. Covalent compound
  • B. A Dative compound
  • C. An Electrovalent compound
  • D. A Non-metal
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63

The periodic table is an arrangement of elements according to their? 

  • A. Oxidation number
  • B. Atomic number
  • C. Mass number
  • D. Nunber of neutrons
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