Chemistry Test-1

A reaction in which two or more substances combine together to form a single product is known as a combination reaction. The reaction between magnesium oxide and water is an example of combination reaction. The reaction is::

\(\mathrm{MgO(s)+H_{2} O(l) \rightarrow Mg(OH)_{2}(aq)}+\)Heat

The reaction with magnesium oxide with water gives magnesium hydroxide and heat.

Aniline, chloroform and alcohol \(\mathrm{KOH}\) on heating gives foul smelling phenyl isocyanide.

\(\mathrm{C _{6}\underset{\text { aniline}}{H_{5}- NH _{2}}+ CHCl _{3}+3 KOH \stackrel{\text { heat }}{\longrightarrow}\underset{\text { Phenyl isocyanide}}{C _{6} H _{5}- NC} +3 KCl +3 H _{2} O}\)

This is Hoffmann's carbyl amines test also called isocyanide test. It is given by aliphatic or aromatic primary amines. This test is not indicated by secondary or tertiary amines.

Blue vitriol is copper sulphate.

Molecular mass of \(\mathrm{CuSO}_{4}=160 \mathrm{~g}\)

\(160 \mathrm{~g}\) of \(\mathrm{CuSO}_{4}\) contains \(63 \mathrm{~g} \mathrm{Cu}\)

So, \(100 \mathrm{~g}\) of \(\mathrm{CuSO}_{4}\) contains \(=\frac{(100 \times 63)}{ 160}\)

\(=39.37 \mathrm{~g}\)

Given that:

Mass of benzene, \((C_6 H_6)=22\)

Mass of Carbon tetra chloride, \((CCl_4)=122\)

We know that:

Mass percentage of Benzene \(\left({C}_{6} {H}_{6}\right)=\frac{\text { Mass of } C_{6} H_{6}}{\text { Total mass of the solution }} \times 100\)

\(=\frac{\text { Mass of } C_{6} H_{6}}{\text { Mass of } C_{6} H_{6}+\text { Mass of } C C l_{4}} \times 100\)

\(=\frac{22}{22+122} \times 100\)

\(=15.28 \%\)

Mass percentage of Carbon Tetrachloride\(\left({CCl}_{4}\right) =\frac{\text { Mass of } C C l_{4}}{\text { Total mass of the solution }} \times 100\)

\(=\frac{\text { Mass of } {CCl}_{4}}{\text { Mass of } C_{6} H_{6}+\text { Mass of } {CCl}_{4}} \times 100\)

\(=\frac{122}{22+122} \times 100\)

\(=84.72 \%\)

Given,

In a fusion process, a proton and a neutron combine to give a deuterium nucleus.

\(m_{n}\) and \(m_{p}\) be the masses of neutron and proton respectively.

Let mass of deuterium nucleus \(=m_{d}\)

So in fusion process some energy is dissipate whose value \(=m c^{2}\)

where,

\(c=\) Speed of light \(=3 \times 10^{8} \mathrm{~m} / \mathrm{s}\)

\(m=\) mass defect

Mass defect \(=\left(m_{n}+m_{p}\right)-m_{d}\)

Thus mass of deuterium nucleus is slightly less than the sum of mass of proton and mass of neutron.

The relation between the pressure and the volume of a gas at constant temperature is given byBoyles law.

According toBoyles law the absolute pressure exerted by a given mass of an ideal gas is inversely proportional to the volume it occupies if the temperature and amount of gas remain unchanged within a closed system.

Mathematically, Boyle's law can be stated as:

\(P \propto \frac{1}{V}\) Pressure is inversely proportional to the volume.

\(P V=k\) Pressure multiplied by volume equals some constant \(k\) where \(P\) is the pressure of the gas, \(V\) is the volume of the gas, and \(k\) is a constant.

We can find out the binding energy by applying the formula, \(B.E .=\Delta m c^{2}\)

Where,

\(\Delta m=\) mass defect

\(c=\) speed of light

Here, it is given that

Mass of neutron \(=1.0087 amu .\)

Mass of proton \(=1.0073 amu.\)

Mass of helium nucleus \(=4.0015 amu.\)

As we know that, in a helium nucleus there are \(2\) neutrons and \(2\) protons.

So theoretical mass will be,

\(=(2 \times 1.0087+2 \times 1.0073)\)

\(=4.032 am u\)

Mass defect \(\Delta m\) given by,

\(\Delta m=(4.032-4.0015) am u\)

\(\Delta m=0.0305 amu\).

Now, by applying the formula, \(B. E. =\Delta m c^{2}\)

\(B.E. =(0.0305 amu) c^{2}\)

Since, \(1 amu=931 MeV / c^{2}\)

Therefore,

\(B. E.=(0.0305) \times 931 MeV\)

\(B. E.=28.4 MeV\).

A polyamide polymer is nylon - 6, 6.

The Rutherford model of an atom explained the behavior of electrons but the explanation was wrong proved by Maxwell’s equation.

According to Maxwell’s equation of electromagnetism, an accelerated electron must continuously emit electromagnetic radiation and loses its energy and fall towards the nucleus. Thus Rutherford model can’t explain this loss of energy.He did not say anything about the arrangements of electrons in the atom.