Jamb 2018 Chemistry Past Questions And Answers
What is the concentration of a solution containing 2g of NaOH in 100cm3 of solution? [Na = 23, O =16, H = 1]
- A) 0.40 moldm^−3
- B) 0.50 moldm^−3
- C) 0.05 moldm^-3
- D) 0.30 moldm^−3
How many atoms are present in 6.0g of magnesium? [Mg=24,N.A=6.02x10^23mol]
- A) 1.20 x 10^22
- B) 2.4 x 10^22
- C) 1.51 x 10^22
- D) 3.02 x 10^22
Which of the following are mixtures? I. Petroleum II. Rubber latex III. Vulcanizer's solution IV. Carbon sulphide
- A) I, II and III
- B) I, II and IV
- C) I and II only
- D) I and IV
Which of the following is an example of a chemical change?
- A) dissolution of salt in water
- B) rusting of iron
- C) melting of ice
- D) separating a mixture by distillation
The radio isotope used in industrial radiography for the rapid checking of faults in welds and casting is?
- A) carbon-14
- B) phosphorus-32
- C) cobalt
- D) iodine-131
According to Charles' law, the volume of a gas becomes zero at
- A) 0°C
- B) -100°C
- C) -273°C
- D) -373°C
The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate (VII) solution is
- A) Na2SO4
- B) Na2SO3
- C) Na2S
- D) Na2CO3
The number of electrons in the valence shell of an element of atomic number 14 is?
- A) 1
- B) 2
- C) 3
- D) 4
On which of the following is the solubility of a gaseous substance dependent? I. Nature of solvent II. Nature of solute III. Temperature IV. Pressure
- A) I, II, III and IV
- B) I and II only
- C) II only
- D) I, III and IV only
Beryllium and Aluminium have similar properties because they
- A) are both metals
- B) belong to the same group
- C) belong to the same period
- D) are positioned diagonally to each other