Question

1. Choose the disproportionation reaction among the following redox reactions.

(a) 3Mg (s) + N

2 (g) → Mg3N2 (s)

(b) P4 (s) + 3 NaOH+ 3H2O → PH3(g) + 3NaH2PO2 (aq)

(c) Cl2 (g)+ 2KI(aq) → 2KCl(aq) + I2

(d) Cr2O3 (s) + 2Al (s) → Al2O3(s) + 2Cr(s)

2. The equivalent mass of potassium permanganate in alkaline medium is

MnO4- + 2H2O+3e- → MnO2 + 4OH-

(a) 31.6

(b) 52.7

(c) 79

(d) None of these

3. Which one of the following is used as a standard for atomic mass.

(a) 6C12

(b) 7C12

(c) 6C13

(d) 6C14

4. Electronic configuration of species M

2+ is 1s

2 2s

2 2p

6 3s

2 3p

6 3d

6 and its atomic weight is 56.

The number of neutrons in the nucleus of species M is

a) 26

b) 22

c) 30

d) 24

5. Assertion : The spectrum of He+ is expected to be similar to that of hydrogen

Reason : He+ is also one electron system.

(a) If both assertion and reason are true and reason is the correct explanation of assertion.

(b) If both assertion and reason are true but reason is not the correct explanation of assertion.

(c) If assertion is true but reason is false

(d) If both assertion and reason are false

6. Which of the following pairs of d-orbitals will have electron density along the axes ?

a) dz2, dxz

b) dxz, dyz

c) dz2, dx2-y

2

d) dxy, dx2-y2

7. Identify the wrong statement.

a) Amongst the isoelectronic species, smaller the positive charge on cation, smaller is the ionic

radius

b) Amongst isoelectric species greater the negative charge on the anion, larger is the ionic radius

c) Atomic radius of the elements increases as one moves down the first group of the periodic

table

d) Atomic radius of the elements decreases as one moves across from left to right in the 2nd

period of the periodic table.

8. Which of the following pairs of elements exhibit diagonal relationship?

a) Be and Mg

b) Li and Mg

c) Be and B

d) Be and Al

9. The element with positive electron gain enthalpy is

a) Hydrogen

b) Sodium

c) Argon

d) Fluorine

10. Assertion : Permanent hardness of water is removed by treatment with washing soda.

Reason : Washing soda reacts with soluble calcium and magnesium chlorides and sulphates in

hard water to form insoluble carbonates

a) Both assertion and reason are true and reason is the correct explanation of assertion.

b) Both assertion and reason are true but reason is not the correct explanation of assertion.

c) Assertion is true but reason is false

d) Both assertion and reason are false​

Answer 1

Answer:

koyel ki teri boli

Explanation:

ku ku ku aha ku ku ku ku

surat hai kitni bholi ......................