Chemistry Test - 21

We have to note that, one mole of electron charge is equivalent to oneFaraday.

Given reaction,

Ca is undergoing oxidation i.e., \({Ca}^{2+}+2 {e}^{-} \rightarrow {Ca}\)

We can observe that, \(40 {~g}\) of \({Ca}\) takes \(2 e^{-}\)charge.

So, if 1 mole of \(C a(40 g) \equiv 2 F\)

Then,\(100 g\) of \(C a =\frac{2}{40}\times 100\)

\(=5F\)

Given reaction is:

\(\mathrm{Cl}_{2}+\mathrm{OH}^{-} \rightarrow \mathrm{Cl}^{-}+\mathrm{ClO}_{3}+\mathrm{H}_{2} O\)

The balanced reaction will be:

\(3 \mathrm{Cl}_{2}+6 \mathrm{OH}^{-} \longrightarrow 5 \mathrm{Cl}^{-}+\mathrm{ClO}_{3}+3 \mathrm{H}_{2} \mathrm{O}\)

Oxidation number of \(C l_{2}=0\)

Oxidation number \(C l\) in \(C l^{-}=-1\)

Oxidation number of\(\mathrm{Cl}\) in \(\mathrm{ClO}_{3}:\)

\(\Rightarrow x+3 \times(-2) =-1\)

\(\Rightarrow x=+5\)

So, \(\mathrm{Cl}_{2}\) is oxidised as well as reduced.

Physical adsorption decreases with increase in temperature.

Physical adsorption is non-directional, reversible, multilayers exothermic process where adsorbate molecules are held on surface of adsorbent by physical forces such as van der Waals forces.

Van der Waals interactions cause these surface atoms to be reactive, causing them to attract liquids, vapors and gases in order to satisfy their atomic force imbalance. The attracted molecules fill in the pores on the surface of the solid when adsorption occurs.

Optical isomerism is exhibited by only those complexes which lack elements of symmetry.

\(\left[ Co \left( NH _{3}\right)_{3} Cl _{3}\right]\) shows facial as well as meridional isomerism. But both the forms contain plane of symmetry.

Thus, this complex does not exhibit optical isomerism.

\(\mathrm{NH}_{4} \mathrm{NO}_{2} \rightarrow 2 \mathrm{H}_{2} \mathrm{O}+\mathrm{N}_{2}\)

\(2\left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4} \rightarrow 2 \mathrm{NH}_{3}+\mathrm{H}_{2} \mathrm{SO}_{4}\)

\(\mathrm{Ba}\left(\mathrm{N}_{3}\right)_{2} \rightarrow \mathrm{Ba}+3 \mathrm{~N}_{2}\)

\(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{Cr}_{2} \mathrm{O}_{7} \rightarrow \mathrm{Cr}_{2} \mathrm{O}_{3}+\mathrm{N}_{2}+4 \mathrm{H}_{2} \mathrm{O}\)

The compound that does not produce nitrogen has by the thermal decomposition is\(\left(\mathrm{NH}_{4}\right)_{2} \mathrm{SO}_{4}\)

Faraday's First Law of Electrolysis states that only, according to this law, the chemical deposition due to flow of current through an electrolyte is directly proportional to the quantity of electricity (coulombs) passed through it.

The reaction of Al is,

\(A l^{3+}+3 e^{-} \rightarrow A l\)

Given,

Current, \(I= 105~amp\)

Now as \(n=3\),

Equivalent weight of \(\mathrm{Al}=\frac{27}{3}=9\)

As per Faraday's first law.

\(W=Z \times I \times t\)

where, \( Z=\frac{E q \cdot w t}{96500}\)

Then, \( t=\frac{W \times 96500}{E q \cdot w t \times I}\)

\(=\frac{50 \times 96500}{9 \times 105}\)

\(=5102.2\)second

\(=1.42\) hours

Given: Vapour pressure of liquid A, \(P_{A} =120~ mm\)

Vapour pressure of liquid B, \(P_{B} =180~ mm\)

Number of moles of liquid A,  \({n}_{{A}}=2\)

Number of moles of liquid B, \({n}_{{B}}=3\)

Therefore,

Mole fraction of liquid A,  \({X}_{{A}}=\frac{n_A}{n_A+n_B}\)\(=\frac{2}{5}\)

Mole fraction of liquid B,  \({X}_{{B}}=\frac{n_B}{n_A+n_B}\)\(= \frac{3}{5}\)

We know that: Vapor Pressure of solution, \({P}={X}_{{A}} {P}_{{A}}+{X}_{{B}} {P}_{{B}}\)

\(=\frac{2}{5} \times 120+\frac{3}{5} \times 180\)\(=48+108\)

\(P=156 {~mm} {~Hg}\)

The treatment of ketones with peracids (RCOOOH) or hydrogen peroxide gives esters by insertion of oxygen. The reaction is called Baeyer-Villiger rearrangement or Baeyer-Villiger oxidation.

\(CCl_4\) is used as a fire extinguisher. The dense, non combustible vapours cover the burning substance and prevent the availability of oxygen around burning material.

The process of benzoylation of compounds containing active hydrogen such as phenol, aniline, alcohol, etc, with benzoyl chloride in the presence of aqueous NaOH is called Schotten-Baumann reaction.

The reaction are as follows:

We know that:

Freezing point \(\propto \frac{1}{\text { Van't Hoff factor }}\)

(A) \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{3} \mathrm{Cl} \rightarrow C_{6} \mathrm{H}_{5} N H_{3}^{\oplus}+C l^{\ominus}\)

Here, Van't Hoff factor, i = 2

(B)\(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2} \rightarrow \mathrm{Ca}^{2+}+2 \mathrm{NO}_{3}^{\ominus}\)

Here, Van't Hoff factor, i = 3

(C)\(\mathrm{} \mathrm{La}\left(\mathrm{NO}_{3}\right)_{3} \rightarrow \mathrm{La}^{3+}+3 \mathrm{NO}_{3}^{\ominus}\)

Here, Van't Hoff factor, i = 4

(D) Glucose does not dissociate. So, it has the minimum number of particles, and therefore, it shows minimum depression in freezing point. So, it has the maximum freezing point.

The instantaneous rate of reaction is defined as the change in concentration of an infinitely small time interval. An instantaneous rate is a rate at some instant in time. The average rate is the average of the instantaneous reaction rate over a period of time during the reaction. It depicts a more accurate value.The instantaneous rate of reaction is the rate at which the reaction is proceeding at any given time.There are two ways to determine the instantaneous reaction rate:

• By using data from experiments and finding the slope of the tangent from the concentration-time graph.
• By using data from experiments by getting their average rate and then determining the reaction rate from the slope of the tangents.

Both the ethers obtained by the two routes have opposite but equal optical rotation

One of the ether is obtained as a racemic mixture

Step II & III both are S2N  reaction and both have inversion Step II has inversion but step III has retention.

According to the question,

It is a \(\beta\)-furanose, thus, a ketohexose.

A ketohexose is a ketone-containing hexose (a six-carbon monosaccharide). The most common ketohexoses, each of which represents a pair of enantiomers (D-isomers and L-isomers), include psicose, fructose, sorbose, and tagatose.

The oxidative rusting of iron under Earth's atmosphere is slow reaction.

The reaction rate (rate of reaction) or speed of reaction for a reactant or product in a particular reaction is intuitively defined as how fast or slow a reaction takes place. For example, the oxidative rusting of iron under Earth's atmosphere is a slow reaction that can take many yearsbut the combustion of cellulose in a fire is a reaction that takes place in fractions of a second. For most reactions, the rate decreases as the reaction proceeds.