JEE MAIN - Chemistry (2020 - 7th January Morning Slot)

1
Two solutions, A and B, each of 100L was made by dissolving 4g of NaOH and 9.8 g of H2SO4 in water, respectively. The pH of the resultant solution obtained from mixing 40L of solution A and 10L of solution B is :
Answer
10.6
2
Chlorine reacts with hot and concentrated NaOH and produces compounds (X) and (Y). Compound (X) gives white precipitate with silver nitrate solution. The average bond order between CI and O atoms in (Y) is.
Answer
1.66to1.67
3
For the reaction :

A($$l$$) $$ \to $$ 2B(g)

$$\Delta U = 2.1\,kcal,\,\Delta S = 20\,cal\,{K^{ - 1}}$$ at 300 K

Hence $$\Delta $$G in kcal is :
Answer
-2.7
4
During the nuclear explosion, one of the products is 90Sr with half life of 6.93 years. If 1 $$\mu $$ g of 90Sr was absorbed in the bones of newly born baby in placed of Ca, how much time, in years, is required to reduce much time, in year, is required to reduce it by 90% if it not lost metabolically.
Answer
23to23.03
5
The number of orbitals associated with quantum number n = 5, ms = +$${1 \over 2}$$ is :
Answer
(B)
25
6
What is the product of following reaction ? JEE Main 2020 (Online) 7th January Morning Slot Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 171 English
Answer
(B)
JEE Main 2020 (Online) 7th January Morning Slot Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 171 English Option 2
7
Consider the following reaction :

JEE Main 2020 (Online) 7th January Morning Slot Chemistry - Compounds Containing Nitrogen Question 169 English
The product 'X' is used :
Answer
(B)
in acid base titration as an indicatior.
8
Given that the standard potentials (Eo) of Cu2+/Cu and Cu+/Cu are 0.34 V and 0.522 V respectively, the Eo of Cu2+/Cu+ :
Answer
(D)
+0.158 V
9
Consider the following reaction :

$${\left( {C{H_3}} \right)_3}CCH\left( {OH} \right)C{H_3}\buildrel {conc.\,\,\,{H_2}S{O_4}} \over \longrightarrow $$

$${\left( {C{H_3}} \right)_2}CHCH\left( {Br} \right)C{H_3}\buildrel {alc.\,\,KOH} \over \longrightarrow $$

$${\left( {C{H_3}} \right)_2}{\rm{ }}CHCH\left( {Br} \right)C{H_3}\buildrel {{{(C{H_3})}_3}{O^\Theta }{K^ \oplus }} \over \longrightarrow $$

$${\left( {C{H_3}} \right)_2}\mathop C\limits_{\mathop |\limits_{OH} } - C{H_2} - CHO\buildrel \Delta \over \longrightarrow $$

Which of these reaction(s) will not produce Saytzeff product ?
Answer
(D)
(c) only
10
The dipole of CCl4, CHCl3 and CH4 are in the order :
Answer
(B)
CH4 = CCl4 < CHCl3
11
Amongst the following statements, that which was not proposed by Dalton was :
Answer
(C)
When gases combine or reproduced in a chemical reactionn they do so in a simple ratio by volume provided all gases are the same T & P.
12
Match the following :
(i) Riboflavin    (a) Beriberi
(ii) Thiamine    (b) Scurvy
(iii) Pyridoxine   (c) Cheliosis
(iv) Ascorbic acid    (d) Convulsions
Answer
(C)
(i)-c, (ii)-(a), (iii)-(d), (iv)-(b)
13
The relative strength of interionic/intermolecular forces in decreasing order is :
Answer
(D)
ion-ion $$>$$ ion-dipole $$>$$ dipole-dipole
14
The IUPAC name of complex [Pt(NH3)2Cl(NH2CH3)]Cl is:
Answer
(A)
Diamminechlorido (methanamine) platinum(II)chloride.
15
1- methyl ethylene oxide when treated with an excess of HBr produces :
Answer
(A)
JEE Main 2020 (Online) 7th January Morning Slot Chemistry - Haloalkanes and Haloarenes Question 116 English Option 1
16
The electron gain enthalpy (in KJ/mol) of fluorine, chlorine, bromine and iodine, respectively are:
Answer
(C)
-333, -349, -325 and -296
17
A solution of m-chloronailimne, m-chlorophenol and m-chlorobenzoic acid in ethyal acetate was extracted initially with a saturated solution of NaHCO3 to give fraction A. The left over organic phase was extracted with dilute NaoH solution tio give fraction B. The final organiic layer was labelled as fraction C. Fractions A,B and C, contain respectively :
Answer
(B)
m-chlorobenzoic acid, m-chlorophenol and m-chloroaniline.
18
The increasing order to Pkb for the following compounds will be : JEE Main 2020 (Online) 7th January Morning Slot Chemistry - Basics of Organic Chemistry Question 176 English
Answer
(C)
(B) < (A) < (C)
19
At 35oC, the vapour pressure of CS2 is 512 mm. Hg and that of acetone is 344 mm Hg. A solution of CS2 in acetone has a total vapour pressure of 600 mm Hg. The false statement amongst the following is :
Answer
(B)
a mixture of 100 ml. CS2 and 100 ml. acetone has a volume < 200 ml.
20
Oxidation number of potassium in K2O. K2O2 and KO2 respectively is :
Answer
(B)
+1, +1 and + 1
21
The theory that can completely/properly explain the nature of bonding in [Ni(Co)4] is :
Answer
(D)
Molecular orbital theory
22
The atomic radius of Ag is closed to :
Answer
(A)
Au