Chemistry tips for JEE Main / MH-CET 2014

JEE एक अजब“रसायन”

1. Competitive examination

2. Two essential ingredients

a. Speed

b. Accuracy

3. 30 MCQ of chemistry

4. JEE Syllabus.5. Chemistry – Syllabus

divided in to 3 fundamental branches.

Chemistry

Physical Inorganic Organic

a. Physical Chemistry : Total unit 10

Important topics :

i. Chemical thermodynamics

ii. Chemical Kinetics

iii. Chemical bonding & molecular Structure

iv. Redox reaction & electro – Chemistry.

b. Inorganic Chemistry

Total units - 08

Important Topics :

i. p – block elements

ii. d & f – block elements

iii. co – ordination compounds.

c. Organic chemistry

Total units – 10

Important Topics :

i. Organic comp. containing oxygen

ii. Organic comp containing halogen

iii. Some basic principles of organic chemistry

Last but not the least

“ Do not try to find out the correct answer

but

try to find out the

CORRECT OPTION”.

1. The complex used as an anti-cancer agent is

(a) cis[PtCI2(NH3)2]

(b) cis-K2[PtCI2Br2]

(c) trans-[Co(NH3)3CI3]

(d) Na2CO3

Ans : a

Solution : Cis-isomer of [Pt (NH3)2 CI2] is used as an anticancer drugs for treating several type of malignant tumours when it is inject into the blood stream the more reactive CI groups are lost so, the Pt atom bonds to a N-atom in guanosine (a part of DNA). This molecule can bond to two different guanosine units and by bridging between them it upsets the normal reproduction of DNA.

( )2

3 2

3

2

Zn 2e Zn s ,     Eº 0.76         

Fe e Fe ,       Eº 0.77         

Cr 3e Cr,          Eº 0.79

1H e H Eº 0.00

2

+ -

+ - +

+ -

+ -

+ ® = -

+ ® = -

+ ® = -

+ ® = -

2. In this which one is the strongest reducing agent

(a) H2 (b) Fe2+

(c) Zn (d) Cr

Ans : d

3. Which of the following is correct for the reaction ∆H=+ve and ∆S=+ve?

(a) Spontaneous at high temperature

(b) Spontaneous at low temperature

(c) Non Spontaneous at all temperatures

(d) Non Spontaneous at high temperature

Ans : a

Solution :

T∆S>∆H for reaction to be spontaneous. When ∆H=+ve and ∆S=+ve, the reaction will be spontaneous at high temperature.

4. Which of the following statements are correct?

1. Order of a reaction can be known from experimental result and not from the stoichiometry of reaction.

2. Overfull molecularity of a reaction may be determined in a manner similar to overall order of reaction.

3. Overall order to reaction,

4. Molecularity of a reaction refers to(i) Molecularity of each of the

elementary steps (slow steps) in a multistep reaction

(ii) Molecularity of that particular step in a single step reactionSelect the correct answer by using the codes given below

m nxA B AB is (m n)+ ® +

(a) 1,3 and 4(b) 1,2 and 3(c) only 1 and 4(d) only 1 and 3Ans : aSolution : Am + Bn → ABx

In this case,Overall order of reaction = m + nHence, statement 2 is wrong.

5. Which of the following reaction is an example of Sandmeyer

reaction

(a) (b)

(c) (d)

Ans : a

6. Match list I with list II and select the correct answer using the codes given below the

Codes(a) 1-C,2-D,3-B,4-E (b) 1-D,2-C,3-E,4-B(c) 1-D,2-C,3-E,4-A (d) 1-D,2-C,3-A,4-E

3 3 0

2 6 0

2 8 0

2 4 0

n(n 2)

Cr (Z 24) : 3d 4s , 3(3 2) 15

Fe (Z 26) : 3d 4s , 4(4 2) 24

Ni (Z 28) : 3d 4s , 2(2 2) 8

Mn (Z 25) : 3d 4s 5(5 2) 35

+

+

+

+

\ m= +

= m= + =

= m= + =

= m= + =

= m= + =

Ans : cSolution :

7. At room temperature, H2O is liquid

while H2S is a gas. The reason is

(a) Electronegativity of O is greater than S

(b) Difference in the bond angles of both the molecules

(c) Association takes place in H2O to

H-bonding while no H-bonding in H2S

(d) both (a) & (c)

Ans : c

Solution :

H2O contain hydrogen bond while no

hydrogen bounding is present is H2S

8. A mixture of benzaldehyde and formaldehyde on heating with aqueous NaOH solution gives

(a) Benzyl alcohol and sodium formate

(b) Benzyl alcohol and methyl alcohol

(c) methyl alcohol and sodium formate

(d) Sodium benzoate and methyl alcohol

Ans : a

Solution :

In Cannizaro reaction when formaldehyde reacts with other aldehydes lacking α-hydrogen, it is always oxidized and other aldehyde is reduced.

NaOH6 5 6 5 2HCHO C H CHO HCOO Na C H CH OH- ++ ¾¾¾® +

V

Thank You…