DELSU Chemistry 2020/2021 Past Questions

Practice each question, then open it to see the full details.

When platinum electrodes are used during the electrolysis of cooper (II) tetraoxoxulphate (V) Solution, the solution gets progressively

A.Acidic
B.Basic
C.Neutral
D.Atmospheric

An element with atomic number twelve is likely to be

A.Electrovalent with a valency of 1
B.Electrovalent with a valency of 2
C.Covalent with a valency of 2
D.Covalent with a valency of 4

What volume of 0.50 M H₂SO₄ will exactly neutralize 20cm₃ of 0.1M NaOH solution?

A.2.0cm³
B.5.0cm³
C.6.8cm³
D.8.3cm³

Which of these has the lowest pH value?

A.Calcium trioxocarbonates
B.Sodium trioxocarbonate (IV)
C.Hydrochloric acid
D.Ethanoic acid

Consecutive members of an alkane homogenous series differ by

A.CH
B.CH₂
C.CH₃
D.C₃H₃

The minimum volume of oxygen required for the complete combustion of a mixture of 10cm³ of CO and 15cm³ of H₂ is

A.25.0cm³
B.12.5cm³
C.10.0cm³
D.5.0cm³

When a solid melts and consequently boils, there is

A.a gradual increase in the average kinetic energy of the particles
B.a sudden decrease in the kinetic energy of the particles
C.a rapid change in the nature of bonding of the components
D.a change in the size of the fundamental particles

The green house effect is a climate condition associated with the presence of excess

A.carbon (IV) oxide
B.hydrogen sulphide
C.ammonia gas
D.nitrogen (II) oxide

Which of the following statements is not correct?

A.carbon exhibits allotropy
B.sulphur exhibits allotropy
C.chlorine exhibits allotropy
D.argon is a noble gas

Which of the following represents a carboxylic acid?

A.R-COOH
B.R-COOR
C.R-COOCOR
D.R-COH