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.
ii and iii only
ii and iv only
iii and iv only
i and ii only
Correct answer is B
Ionization energy and electron affinity increase across a period, and decrease down a group.
2.0 moldm\(^{-3}\)
0.25 moldm\(^{-3}\)
1.0 moldm\(^{-3}\)
0.5 moldm\(^{-3}\)
Correct answer is A
Given the Mass of the salt = 58.5g
Volume = 250 cm\(^3\) = 0.25 dm\(^3\)
Mass concentration = \(\frac{Mass}{Volume}\)
= \(\frac{58.5}{0.25}\) = 234 gdm\(^{-3}\)
Solubility (in moldm\(^{-3}\) = \(\frac{234}{111} \)
= 2.11 moldm\(^{-3}\)
\(\approxeq\) 2.0 moldm\(^{-3}\)
Fractional crystallization
Fractional distillation
Filtration
Evaporation
Correct answer is A
No explanation has been provided for this answer.
Which of the following does not support the fact that air is a mixture?
the constituents of air are in a fixed proportion by mass
it cannot be represented with a chemical formula
the constituents of air can be separated by physical by physical means
none of the above
Correct answer is D
No explanation has been provided for this answer.
Which of the following statements about catalyst is false?
biological catalysts are called enzymes
catalyst do not appear in the balanced equation
catalyst reduce the activation energy for a reaction
catalysts do not alter the mechanism of the reaction and never appear in the rate low
Correct answer is D
No explanation has been provided for this answer.