CIE Chemistry (US-0439): Specimen Questions with Answers 189 - 191 of 240

Question number: 189

Short Answer Question▾

Write in Short

Gasoline is a mixture of hydrocarbons containing between 5 and 10 carbon atoms. Four of these hydrocarbons are shown below

Which one of these structures, A, B, C or D, has the highest relative molecular mass?

You are not expected to do any calculations.

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Explanation

Correct Option is option B because in option B there is the longest chain of hydrocarbon so it has highest relative molecular no.

Question number: 190

Short Answer Question▾

Write in Short

Aluminum and gallium are in Group III of the Periodic Table.

Gallium is a metal. Describe three physical properties of gallium which are typical of most metals.

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Explanation

  1. Gallium is a metal because gallium can conduct electricity and heat which is a property of metal.

  2. Gallium is a metal of because melting point of gallium is also high as compared to liquid and gas which is a property of metal.

  3. gallium is the only one that is neither highly reactive nor highly toxic and can therefore be used in metal-in-glass high-temperature thermometers which is also the property of metal.

Question number: 191

MCQ▾

Question

________ completely ionise to produce a high concentration of ions.

Choices

Choice (4) Response

a.

Strong bases

b.

Strong acids

c.

Weak bases

d.

Weak acids

Answer

b.

Explanation

Strong acids completely ionise to produce a high concentration of ions. E. g, etc.