Chemistry: Topic-wise Test- 2 - NEET

The reactivity order towards H₂ is
cis > iso > trans i.e in option A the alkene is cis.

1,3 -hexadiene is a conjugated diene, hence it is more stable than the first compound. The heat of hydrogenation decreases as the stability of the molecule increases. The stability of 13 hexadiene is more than that of a compound which contain two double bonds.

Total energy to break 3 bond in benzene is 87 [51+36].
So to break one bond i.e. in cyclohexaene is 87/3= 29kcal/mol.
And to break 2 bond i.e.in cyclohexadiene is 29*2= 58 kcal/mole.

At the cathode (C), water is reduced to hydroxide and hydrogen gas. The net process is the electrolysis of an aqueous solution of NaCl into industrially

Electrolysis of aqueous sodium chloride yields hydrogen and chlorine, with aqueous sodium. Chlorine gas bubbles out of the melt above the anode.

H₂O₂ is the special concentration terms.10 volume of H₂O₂ means that 1ml of H₂O₂ gives 10 ml of O₂.
For example, if it was mentioned 30 volume of H₂O₂, then its means that 1ml of H₂O₂ gives 30ml of O₂.

Chemical properties won't change in case of isotopes. Therefore answer is D.

According to the first law of thermodynamics,
∆Q=∆U+∆W and for a cyclic process, change in internal energy(∆U) is zero. Hence ∆Q=∆W where ∆Q is the heat absorbed and ∆W is the work done. Therefore heat absorbed is 50 kJ

It should be equal to T, not (-T)

Rhombic sulphur is the standard state of sulphur or in its pure state.And in standard state it is taken as zero.

A state function is the property of the system whose value depends only on the initial and final state of the system and is independent of the path.Heat (q) and work (W) are not state functions being path dependent.

Without calculation one can also say that the answer is a because acid has a ph value less than 7.

Normality volume = (0.1) (0.001)
Normality volume = 0.0001 L
Volume of solution = Volume of NaCl + Volume of HCL
Volume of solution = 1 + 0.001
Volume of solution = 1.001 L
Since NaCl is a salt and is neutral so it does not effect pH of a solution.
Now,
Normality of HCL in a resulting solution = 0.0001 / 1.001
Normality of HCL in a resulting solution = 0.0001 N
So,
pH = - log [H⁺]
pH = - log (0.0001)
pH = 4
which shows that the pH of the resulting solution is 4

Lets calculate the pOH first,

Since 1 mol Ba(OH)2 gives 2 moles of OH- 0.2 moles will give 0.4 mol OH-

However its 90% ionised and hence [OH-] = 0.36 M 

So pOH = -log [0.36]

= 0.443

pH = 14-0.443

= 13.55

Concentrations of the ions:

The dissociation reaction for PbCl_2​ in water is write as,

PbCl₂​→Pb₂+(aq)+2Cl−(aq)

The maximum concentration of PbCl₂ in water is 0.01 M

We can find concentration of the ions using the stoichiometry from the above reaction.

The concentration of Pb²⁺ ion is 0.01 M and concentration of Cl⁻ ion is 2×0.01=0.02M.

Solubility product:

The solubility product of PbCl₂​ can be written as,

KSP​=[Pb²⁺][Cl]⁻²

Let us insert in the concentrations of Pb and Cl.

KSP​=(0.01)(0.02)

Ksp =4.0×10−6

Concentration of Pb²⁺ using common ion effect:
WhenPbCl₂​ is dissolved in 1MNaCl, there is a common ion Cl−. This decreases the solubility of PbCl₂​ due to the common ion effect.
The concentration of Cl− in 0.1MNaCl is 0.1. Let us plug in this value to find the new concentration of Pb²⁺ ion.

Ksp=[Pb²⁺][Cl⁻]²

4×10−6=[Pb²⁺](0.1)²

[Pb²⁺]=0.014×10^−6​

[Pb²⁺]=0.0004M=4×10−4 M

AgCl is precipitated only when [Ag+][Cl-] > Ksp
On mixing equal volumes of two solutions, concentration becomes halved.

Ammonium hydrogen sulphide is contained in a closed vessel at 313K when total pressure at equilibrium is found to be 0.8 atm.

NH₄​HS(s)⇌NH₃​(g)+H₂​S(g)

P_NH3​​=P_H2​S​=P

Total pressure P_NH3​​+P_H2​S​=P+P=2P

But total pressure is 0.8 atm.

2P=0.8

P=0.4 atm

P_NH3​​=P_H2​S​=P=0.4 atm

The value of the equilibrium constant for the reaction,is Kp​=P_NH3​​×P_H2S​

Kp​=0.4×0.4

Kp​=0.16

Melting point order is para > ortho > meta on basis of symmetry . So option b is correct.

When alkenes react with Br2 in presence of CCl₄ it gives vicinnyl dibromides (1 2 dibromide )

The major product is tert butyl chloride as firstly isobutylchloride is formed but then hydride shift takes place due to which chlorine shift to more stable tertiary carbocation and hence the product is tert butyl chloride.

SO₂ can act as both oxidizing as well as reducing agent since it has +4 oxidation state which is exactly between
its highest oxidation state +6 and lowest oxidation state +2 ,
Thus it can change its oxidation number either from +4 to-2(reduction) and +4 to+6 (oxidation)

Redox reactions are characterized by the transfer of electrons between chemical species, most often with one species undergoing oxidation while another species undergoes reduction.

2KI+Cl₂​⟶2KCl +I_2​​

It is an example of a redox reaction.

Hence, option C is correct.

The net charge on the compound should be zero. Or the sum of oxidation states = 0.

Given: oxidation number of X is +2, Y is +5 and Z is -2.

In XYZ₂​:

2+5+2×(−2)=+3

In Y_2​(XZ₃​)₂​:

2×5+2×(2+3×(−2))=+2

In X₃​(YZ_4​)₂​:

3×2+2×(5+4×(−2))=0

In X_3​(YZ₄​)₂​:

3×2+2×(5+4×(−2))=0

In X₃​(Y₄​Z)₂​:

3×2+2×(4×5−2)=42

A compound contains atoms X, Y and Z . The oxidation number of X is +2 , Y is +5 and Z is -2.

The possible formula of the compound is X_3​(YZ₄​)_2​.

Carbon has three well known allotropes which are graphite, daimond and buck minster fullerene.

Since the layers are only weakly attracted to each other, they can easily slide past one another. This is why graphite is used in pencil lead. The distance between layers is 335 pm. Carbon atoms in diamond are covalently bonded and are arranged in a three-dimensional tetrahedral structure.

Coal gas contains a variety of calorific gases including hydrogen, carbon monoxide, methane, ethylene and volatile hydrocarbons together with small quantities of non-calorific gases such as carbon dioxide and nitrogen.

H₂SO₄ + HCOOH → CO + H₂SO₄•H₂O. 
Sulfuric acid react with formic acid to produce carbon monoxide and hydrate sulfuric acid.

CO is the gas used for purification of nickel and this process is called Mond process.

The elments of the boron family adopts oxidation states +3 or +1. The +3 oxidation states are favorable except for the heavier elements, such as Tl, which prefer the +1 oxidation state due to its stability; this is known as the inert pair effect.

Boron reacts with fused sodium hydroxide to form sodium borate and hydrogen.
B + 6NaOH →→ 2Na₃BO₃ + 3H₂

B₂H₆ + 6Cl₂ → 2BCl₃ + 6HCl

Diborane react with chlorine to produce boron(III) chloride and hydrogen chloride...

Serpeck process is a method of purification of Bauxite ore containing silica (SiO₂​) as the main impurity.

The reaction involved are-

Al₂​O₃​.2H_2​O+3C+N₂​⟶2AlN+3CO+2H₂​O

2AlN+6H₂​O⟶2NH_3​+Al(OH)₃​

Anhydrous aluminium chloride is hydrolised partly with the moisture in the atmosphere to give HCl gas. This HCl gets combine to moisture in air giving white fumes. So white fumes appear by hydrolysis.

According to van der Waals equation for 1 mole of a real gas
(P+(a/V²)​)(V−b)=RT
If a and b are small, a/V² and b can be neglected as compared to P and V and the equation reduces to PV=RT. Hence, a real gas will resemble an ideal gas when constants a and b are small.

RMS speed = √(3RT/M) where, T is temperature, R is universal gas constant and M is molecular mass of gas
Here molecular mass is same for N2 (14x2=28) and CO (12+16=28) so rms speed will also b same for them as rest all is constant 

Pressure at the base of a liquid column =hdg

Here h=height of the column

d=density of liquid

g=acceleration due to gravity

since the column is inclined at an angle θ the vertical height=l cosθ

Pressure=lcosθ*d*g

             =ldgcosθ

Here P=d=density

so option (d) is correct

=pgl cosθ