CIE Chemistry (US-0439): Specimen Questions with Answers 65 - 68 of 240

Question number: 65

MCQ▾

Question

Some white anhydrous sulfate powder is put into a beaker of water and stirred.

What would show that the process was exothermic?

Choices

Choice (4) Response

a.

A blue solution is formed

b.

The beaker feels cooler

c.

The beaker feels warmer

d.

The powder dissolves in the water

Answer

a.

Explanation

Correct option is A i. e. A blue solution is formed. Because when then the solution turns blue and a little heat is evolved so this shows that it is a exothermic process.

Question number: 66

MCQ▾

Question

The atomicity of sodium molecule is three.

Choices

Choice (4) Response

a.

Two

b.

Four

c.

One

d.

Three

Answer

c.

Explanation

The number of atoms of an element that join together to form a molecule of that element is known as atomicity of that molecule.

Sodium (Na) molecule is made of one atom of sodium. So it’s a monatomic molecule.

So it’s atomicity is one.

Question number: 67

Short Answer Question▾

Write in Short

  1. Alkenes and simpler alkanes are made from long-chain alkanes by cracking. Complete the following equation for the cracking of the alkane .

Explanation

Question number: 68

MCQ▾

Question

Organic compounds may have names ending in -ane, -ene, -ol or -oic acid.

How many of these endings indicate the compounds contain double bonds in their molecules?

Choices

Choice (4) Response

a.

1

b.

2

c.

3

d.

4

Answer

a.

Explanation

Correct option is A i. e. 1 because only –ene represents double bond and –ane represents single bond and –ol or –oic acid is the functional group.