Today's Test - Chemistry

As per the modern periodic law,the physical and chemical properties of elements are periodic functions of their

Atomic volume
Electronic configuration
Atomic weight
Atomic size

DIRECTION : These are Assertion-Reason type question.Question contains two statements:Statement-1 (Assertion) and Statement-2 (Reason). Answer these questions from the following four options.

Statement-1 :Hydrogen peroxide forms two series of salts called peroxides.
Statement-2 :Hydrogen peroxide molecule has two replaceable hydrogen atom

Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement -1
Statement-1 is True, Statement -2 is True ; Statement-2 is NOT a correct explanation for Statement - 1
Statement-1 is True, Statement- 2 is False
Statement-1 is False, Statement -2 is True

Solution

Both Assertion (A)and reason (R) are true. Hydrogen peroxide forms two series of salts called hydro peroxides and peroxides.

A bottle of dry ammonia and a bottle of dry hydrogen chloride connected through a long tube are opened simultaneously at both ends the white ammonium chloride ring first formed will be

at the centre of the tube.
near the hydrogen chloride bottle.
near the ammonia bottle.
throughout the length of the tube.

Solution

\(Rate \; of \; diffusion \propto \sqrt{\frac{1}{Molecular \; mass}}\)

∵ Molecularmass of HCl > Molecular mass of NH₃

∴ HCl diffuses at slower rate and white ammonium chloride is first formed near HCl bottle.

The value of P° for benzene is 640 mm of Hg.The vapour pressure of solution containing 2.5 gm substance in 39 gm.benzene is 600 mm of Hg the molecular mass of X is –

65.25
130
40
75

Solution

There are three closed containers in which equal amount of the gas are filled.

If all the containers are placed at the same temperatures, then find the incorrect options –

Pressure of the gas is minimum in (III) container
Pressure of the gas is equal in I and II container
Pressure of the gas is maximum in (I)
The ratio of pressure in II and III container is 4 : 3

Solution

n, T same hence P ∝ ¹⁄_V,

V₁ = 1000 cm³

V₂ = π(10)² × 10 = 1000πcm³

V₃ = ⁴⁄₃π(10)³ = ⁴⁄₃ π 1000 cm³

∴ Pressure of the gas is minimum in (III) container, pres-sure of the gas is maximum in (I),

The ratio of pressure in II and III container is 4 : 3

The IUPAC name of the compound CH₃OCH₂CH₂CH₂O₂CH₂ CH₂ is :

3-ethoxy-1-methoxypropane
1-ethoxy-3-methoxypropane
2, 5-dioxyhexane
ethoxypropane oxymethane

Solution

\(CH_{3}-O-\overset{1}{CH}_{2}-\overset{2}{CH_{2}}-\overset{3}{CH_{2}}-O-CH_{2}CH_{3}\)

3-ethoxy-1-methoxypropane

Coordination numbers of Zn2+ and S2– in the crystal structure of wurtzite are

4, 4
6, 6
8, 4
8, 8

Solution

Wurtzite has face centred cubic structure in which each Zn²⁺ ion is attached to four S^2- ions and each S^2- ion remains in contact with four Zn²⁺ ions. Hence coordination number of each ion is 4.

Which pair of isomerism is not possible together?

Ring-chain and functional
Geometrical and optical
Metamerism and functional
Metamerism and chain

Solution

Metamerism shown among compounds of the same functional group.

Which compound among the following gives positive iodoform test ?

1.Ethanol 2.Ethanal

3.1-Butanol 4.2-Butanol

5.Phenyl ethanol

1, 2 and 5
1, 3 and 4
1, 2 and 3
1, 2 and 4

Solution

Aniline is treated with bromine water to give an organic compound ‘X’which when treated with NaNO₂ and HCl at 0° C gives a water soluble compound ‘Y’. Compound ‘Y’ on treatment with Cu₂Cl₂ and HCl gives compound ‘Z’.Compound ‘Z’ is

o-bromochlorobenzene
p-bromochlorobenzene
2, 4, 6-tribromophenol
2, 4, 6-tribromochlorobenzene

Solution

The molarity of pure water is :

50 M
18 M
55.6 M
100 M

Solution

Solution

Carbon monoxide (CO) is harmful to man because

it forms carbolic acid
it generates excess CO₂
it is carcinogenic
it competes with O₂ for haemoglobin

Solution

CO is highly toxic and impairs respiration. CO combine with haemoglobin of blood and reduces its O₂ carry capacity.

Which of the following statements do not form a part of Bohr’s model of hydrogen atom ?

Energy of the electrons in the orbits are quantized
The electron(s) in the orbit nearest to the nucleus has thelowest energy
Electrons revolve in different orbitsaround thenucleus
The position and velocity of the electrons in the orbitcannot be determined simultaneously

Solution

This statement is known as uncertainty principle which was given by Heisenberg it is not a Bohr’s postulate.

Which one of the following on hydrolysis produces aketone?

Isobutylidene chloride
Secondarybutylidene chloride
Benzylidene chloride
Ethylidene chloride

Solution

DIRECTIONS: Read the passage given below and answer the question that follow :A hydrocarbon (X) of the formula C₆H₁₂ does not react with bromine water but react with bromine in presence of light, forming compound (Y). Compound (Y) on treatment with Alc. KOH gives compound [Z] which on ozonolysis gives (T) of the formula C₆H₁₀O₂. Compound (T) reduces Tollens reagent and gives compound (W). (W) gives iodoform test and produce compound(U) which when heated with P₂O₅ forms a cyclic anhydride (V)

Solution

The organometallic compound is :

Ti(OCOCH₃)₄
Ti₂(C₂H₄)₄
Ti(O₆CH₅)₄
Ti(O₂CH₅)₄

Solution

Organometallic compound is (b)as it contains metal-carbon bonds.In others, direct link of carbon with metal is not present.

Value of universal gas constant(R) depends upon

Number of moles of gas
Volume of gas
Temperature of gas
None of these

Solution

Value of gas constant depends only upon units of measurement.

These are Assertion-Reason type questions. Each of these question contains two statements:Statement-1 (Assertion) and Statement-2 (Reason). Answer these questions from the following four options.

Statement-1 :CHCl₃ is stored in dark bottles.

Statement-2 :CHCl₃ is oxidised in dark.

Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1
Statement-1 is True, Statement-2 is True ; Statement-2 is NOT a correct explanation for Statement-1
Statement-1 is True, Statement-2 is False
Statement-1 is False, Statement-2 is True

Solution

CHCl₃ is stored in dark bottles to prevent oxidation of CHCl₃ in presence of sunlight.