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Question 1. The weight of Na+ in the solution of Na2 SO4 is 92g . Find molality of Na+ per kg of water?
Given: Na2 SO4. ⎯⎯→ Na+ = 92 gm
To find: Molality of Na+ per kg of water
Formula: Molality per kg = (Wt of solute) / (molecular wt of solute wt of solvent(kg)) = 92/23 = 4
Question 2. Which of the following options is correct for given curve?
According to Freundlich isotherm
Where, 1/n 0 to 1
(x/m) = k(P) 1/n
Slope= 1/n = (From graph Slope= tan 2/4)
2/4 n = 1/ n
Question 3. 20 ml of 0.1 M H2SO4 is added to 30 ml of 0.2 M NH 4OH then calculate pH of resultant solution.
(Given that P Kb of NH4OH is 4.7)
NH4OH = 30ml,M
H2SO4+2 NH4OH⎯⎯→(NH4)2SO4+ H2O
20 × 0.1 30 × 0.2
t = 0 2 mm 6 mm 0 mm 0 mm
t = t 2 – 2 6 – 2 × 2
= 0 mm 2 mm 4 mm 2 mm
It is a complete Neutralisation ,r x n So Buffer formula is applied
POH = Pkb + log10(Salt/Base)
= 4.7 + log10(4/2)
= 4.7 + log10(2)
P OH = 5
PH = 14 -5 = 9
PH = 9
Question 4. Which of the following is not correct about Henry’s law.
According to Henry’s law
P = KB x Solubility
P = Partial pressure of gas
KH = Henry’s constant
Solubility 1 KH (KH is different for different gas)
According to this expression, if the solubility of gas increases the value of KH decreases.
Question 5. 2A + B → Product
Rate (M min-1 )
6.93 x 10-3
6.93 x 10-3
1.386 x 10-2
Time when concentration of A becomes half
Rate = k[A] x [B] y
6.93 x 10-3 = k(0.1)x (0.20)y… (1)
6.93 x 10-3 = k(0.1)x (0.25)y… (2)
1.386 x 10-2 = k(0.2)x (0.30)y… (3)
Divide equation (1) by (2)
1= (0.20/0.25)y y = 0
Divide equation (1) by (3)
(1/2) = (1/2)x x 1
From equation (i) and (iii) we get x =1, so it is first order with respect to A.
6.93 x 10-3 = k(0.1 )
k = 6.93 x 10-2 min-1
t 1/2 = 0.693/k
t 1/2 = 0.693/(6.93 x 10-2) =10
Question 6.0.05 F charge is passed through a lead storage battery. In the anodic reaction, what is the amount of PbSO4 precipitated (Molar mass of PbSO4 is 303 g/mol)
Charge = 0.05 F
Amount of PbSO4 precipitated = W
Molar mass of PbSO4 = 303 g/mol
According to Faraday’s 1st law of electrolysis
1 st method
W = E x Q
E = M/2; Q= 0.05
W = (303 x 0.05)/2 = 7.6 g
2 nd method:
Pb(s) + SO4 2- ⎯⎯→ PbSO4 + 2e-
For 2f current passed, PbSO4 deposited = 303 g/mol
For 0.05 F current passed, PbSO4 deposited = W
W = (303x 0.05)/2= 7.6 g
Question 7. In hydrogen emission spectrum electron transition takes place from n = 8 to n = nf. If we plot this graph of ῡ vs (1/nf2 ). Which of the following statement is correct.
Transition state = n = 8 to n = nf
Graph (ῡ vs (1/nf2 ))
ῡ = RH z2[(1/n12) – (1/n22)] (Z = 1 for hydrogen emission spectrum)
ῡ = RH 12[(1/nf2) – (1/82)]
Comparing it with y = mc2
Slope = RH
Question 8. Given a mixture with 0.5 mole of gas A and X moles of gas B. Total pressure is 200 pa at 1000 k temperature in a vessel of volume 10m3. Then, find x. (R is universal gas constant).
Given: Mix – Gas A + Gas B
0.5 mole x mole
Total pressure = 200 pa
T = 1000 k V = 10 m3
x = ?
Pv = nRT
200 x 10 = (0.5+ x )R x 1000
2 = (0.5 + x) R
(2/R) -0.5 = x
(2/R) – (1/2) = x (4-R/2R) = x
Question 9.Whichof the following are isotope of hydrogen
Protium, Deutrium and Tritium
Question 10. Arrange the following in order of Kb value
This nitrogen contains 3 bond and its hybridisation is SP2 . Since the lone pair is delocalised inside the ring it doesn’t take part in hybridisation and make this compound to be aromatic in nature
Question 11.Product ‘x’ major will be
It involves Electrophilic addition of alkenes, followed by Nucleophilic substitution mechanism.
Question 12. Arrange the following in order of K a value
Based on the order of – I effect.
More the -I effect greater its acidic strength.
NO2 CN F Cl
Hence the correct order is R > S > P > Q
Question 13.Presence of which makes water unsuitable for drinking.
Fact from NCERT
Presence of 0.05 Mn ppm concentration makes water unsuitable for drinking
Question 14. Which of the following is strongest acid
Order lies with –I and –M effect. -I and –M effect in CN is more when compared to Cl, I and Br. After losing H+ the negative ion on the C will be delocalized to CN making it more stable and acidic.
Ans: CH (CN)3
Question 15. Which of the following alkaline earth metal nitrate does not crystalline with water of crystallization?
•It depends on the polarization power of cation.
• The atom which is having larger size will have lesser polarization power and does not have water of crystallization.
• Ba 2+ ion is larger in size in comparison to Ca 2+ Mg 2+ and Sr 2+ ion.
• Ba(NO3)2 is the correct option.
Question 16. Which of the following ore contains iron and copper
Malachite – Copper ore CuCO3 Cu(OH)2 .
Azurite – Copper ore 2CuCO3 Cu(OH)2
Copper pyrite – Cu+ Fe CuFes2 - Copper + Iron ore
Question 17. Considering MOT comment on the stability:
Li2+ → 5e +
Bond order = (Nb –NA)/2 = (3-2)/2 =1/2
Li2+ → 5e +
Bond order = (Nb –NA)/2 = (4-3)/2 =1/2
Both Li2+, + Li2− have same bond order. Unlikely 0.5 bond order does not exist so both Li2+ and Li2− are unstable.
If option were given as
1) Li2+ > Li2–
2) Li2+ < Li2–
3) Li2+ = Li2–
4) None of these
We can consider if same B.O is present, the species which is having lesser number of electrons present in antibonding orbital will be more stable so Li2+ > Li2− .
Question 18. Which of the following property in a group decrease down the group and increase down the group respectively.
On moving down, the group electro negativity decreases. On moving down, the group atomic shell increases there by atomic radius increases.
Question 19.isothermal expansion of gas for two temperature T1 and T2 (T2 T1) Graph versus (
w = - nRT ln (vf/vi) = → constant is given same in all case.
Take magnitude forW.
Lines cannot intersect and Intercept will be negative.
Question 20. Which of the following properties is/are true for a silicone polymer?
A) Thermally resistant and have low dielectric constant
B) Resistant towards oxidation and used in grease
D) Hydrophobic in nature
All, A, B, C and D are true for a silicone polymer
Question 21. Which of the following is a piezo electric material?
Piezoelectric → these are the material that produce electrical potential when pressure is applied on parallel and perpendicular phases.
EX - Quarts.
Question 22.Aluminium exist in +3 stable whereas thallium exists in both +1 & +3 oxidation state. Reason for this is;
Due to inert pair effect thallium exist both 1+ and +3 oxidation state. But Thallium is stable in +1 oxidation state.
Question 23. Maximum spin only magnetic moment for transition metal complex may be
In Transition metal complex maximum number of unpaired electron possible is 5 and it will be present in d sub shell
Formula → =
n no of impaired electron
Question 24. Match the following drugs with correct functional group test
A) Chloroxylenol P) Carbylamines
B) Penicillin Q) Baeyer’s reagent
C) Sulpha Pyridine R) FeCl3 test
D) Norethindrone S) Sodium hydrogen sulphate
Penicillin contains COOH group – respond to sodium hydrogen sulphate test.
Chloroxylenol contains OH group – respond to neutral FeCl3 test
Sulpha pyridine NH2 group – respond to carbylamines test
Norethindrone C ≡ CH – respond to Bayers test
Question 25.Product X → Y will be
Question In the given image, X will be
Classical reduction ⎯⎯→ Aldehyde is formed.
Question 27.Arrange the following amino acids in order of their PKa order.
Lysine, Aspartic acid, Arginine, Glycine.
Question 28.Write the product of given reaction:
It involves nucleophilic substitution reaction (SN2 ) followed by oxidation with oxidising agent and removal of water molecule.
Question 30.Consider the compound A [Cr (H2O)6] Cl3 ; yellow B [Cr(NH3)6] Cl3 violet. Then which of the following is incorrect.
The crystal field splitting parameter can’t be measured by wavelength of yellow and violet colours for (A) & (B) respectively.