JAMB UTME - Chemistry - 2019

Elements X and Y have electronic configurations \(1s^2 2s^2 2p^4\) and \(1s^2 2s^2 2p^6 3s^2 3p^1\) respectively. When they combine, the formula of the compound formed is

Consider the reaction

\( \mathrm{A(s) + 2B(g) \rightarrow 2C(aq) + D(g)} \)

What will be the effect of a decrease in pressure on the reaction?

If acidified Potassium Dichromate(VI) (\(\mathrm{K_2Cr_2O_7}\)) acts as oxidizing agent, color changes from

The heat of formation of ethene, \( \mathrm{C_2H_4} \) is 50 \( \mathrm{kJmol^{-1}} \), and that of ethane, \( \mathrm{C_2H_6} \) is -82\( \mathrm{kJmol^{-1}} \). Calculate the heat evolved in the process:

\[ \mathrm{C_2H_4 + H_2 \rightarrow C_2H_6} \]

The emission of two successive beta particles from the nucleus \( {}^{32}_{15}\mathrm{P} \) will produce

At 27°C, 58.5g of sodium chloride is present in 250cm\(^3\) of a solution. The solubility of sodium chloride at this temperature is?

(molar mass of sodium chloride = 111.0gmol\(^{-1}\))

The combustion of carbon(ii)oxide in oxygen can be represented by equation.

\(2\mathrm{CO} + \mathrm{O}_2\ ?\ 2\mathrm{CO}_2\)

Calculate the volume of the resulting mixture at the end of the reaction if \(50\mathrm{cm}^3\) of carbon(ii)oxide was exploded in \(100\mathrm{cm}^3\) of oxygen

A solution X, on mixing with \( \mathrm{AgNO_3} \) solution gives a white precipitate soluble in aqueous \( \mathrm{NH_3} \), a solution Y, when also added to X, also gives a white precipitate which is soluble when heated solutions X and Y respectively contain

A secondary alkanol can be oxidized to give an

The cost of discharging 6.0g of a divalent metal, X from its salt is ₦12.00. What is the cost of discharging 9.0g of a trivalent metal, Y from its salt under the same condition?

[X = 63, Y = 27, 1F = 96,500C]

Consider the reaction: \( \mathrm{A + 2B(g) \rightleftharpoons 2C + D(g)} \) (\( \Delta H = +\mathrm{ve} \))

What will be the effect of decrease in temperature on the reaction?

Consider the equation below:

\(\mathrm{Cr_2O_7^{2-} + 6Fe^{2+} + 14H^+ \rightarrow 2Cr^{3+} + 6Fe^{3+} + 7H_2O}\).

The oxidation number of chromium changes from

An element Z contains 80% of \( {}^{16}_{8}\mathrm{Z} \) and 20% of \( {}^{18}_{8}\mathrm{Z} \). Its relative atomic mass is

\( \mathrm{SO_3} \) is not directly dissolved in water in the industrial preparation of \( \mathrm{H_2SO_4} \) by the contact process because

By what amount must the temperature of 200cm\(^{3}\) of Nitrogen at 27°C be increased to double the pressure if the final volume is 150cm\(^{3}\) (Assume ideality)

The hybridization in the compound \( \mathrm{CH_3-CH_2-C\equiv H} \) is

In the reaction:

M + N → P

ΔH = +Q kJWhich of the following would increase the concentration of the product?

How many alkoxyalkanes can be obtained from the molecular formula \( \mathrm{C_4H_{10}O} \)?