Post Utme Chemistry Past Questions and Answers

Question 1141:

What happens to the conductivity of an electrolyte as its concentration reduces?

A. Increases
B. Decreases
C. Is unaffected
D. Becomes resistivity

Question 1142:

If the cost of electricity required to deposit $1g$ of aluminum is $\mathrm{\#}4.00$, how much would it cost to deposit $24g$ of copper' $[A]=27,Cu=64]$

A. #27.02
B. #37.02
C. #47.02
D. #57.02

Question 1143:

The ov erall reaction in an electrochemical cell is $M{g}_{(51}\cdot C{u}_{(\text{(a) })}^{2+}\to M{g}_{(aq)}^{2+}+C{u}_{(s)}$ *
What is the symbolic representation of the cell?

A. $M{g}_k,M{g}_{\text{(aq) }}^{2+}\Vert C{u}_{(a-1)}^{2\ast }/C{u}_{(3)}$
B. $M_{g_{ni1}}/M{g}_{(i)}^{2+}\Vert C{u}_{(s)}^{2+}/C{u}_{(\text{aq })}$
C. $C{u}_{(\text{aq }}^{2+}/C{u}_{(s)}\Vert M{g}_{(s)}/M{g}_{(\text{(a) }}^{2+}$
D. $C{u}_{(s)}/C{u}_{(sq)}^{2+}\Vert M{g}_{(aq)}^{2+}/M{g}_{(s)}$

Question 1144:

Which of the following metals can be used as sacrificial cathode for preventing corrosion of a length of iron pipe?

A. Ag
B. Cu
C. Mg
D. Mn

Question 1145:

A particle that contains 8 protons, 9 neutrons and 7 electrons could be written as ____________

A. ${}_8^{16}O$
B. ${}_8^{17}{O}^{-}$
C. ${}_9^{17}{O}^{-}$
D. ${}_8^{17}O$