Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
Chemical reactions occurs when the colliding reactants have energy that is
less than the activation energy
greater than the activation energy
greater than the energy of the product
less than the energy of effective collision
Correct answer is B
The energy of the reactants must be more than the activation energy in order for product to be formed.
Soluble salts can be prepared by the following methods except
neutralization
reaction of an acid with trioxocarbonate(IV) salt
double decomposition
reaction of an acid with electropositive metals
Correct answer is C
Soluble salts cannot be produced by double decomposition( precipitation of an insoluble salt)
The property of a chemical reaction that is affected by the presence of a catalyst is
activation energy
free energy
equilibrium position
enthalpy change
Correct answer is A
The activation energy is the amount of energy that is required to form products in a reaction. The presence of a catalyst helps to speed up the reaction such that the energy needed for the reaction is reduced.
0.2\(gdm^{-3}\)
1.0\(gdm^{-3}\)
2.0\(gdm^{-3}\)
5.0\(gdm^{-3}\)
Correct answer is B
Solubility in \(gdm^{-3}\) = \(\frac{mass of salt in gram}{volume of liquid in dm^{3}}\)
200\(cm^{3}\) = \(\frac{200}{1000} dm^{3} = 0.2dm^{3}\)
Solubility = \(\frac{0.2g}{0.2dm^{3}}\)
= 1.0\(gdm^{-3}\)
Solubility curve can be used in the determination of the
amount of crystals formed
amount of solvent that can be recovered
amount of solid drugs in a given solution
temperature of the solution
Correct answer is C
No explanation has been provided for this answer.