An element X has the following isotopic Composition ²⁰⁰X = 90%, ¹⁹⁹X = 8% and ²⁰²X = 2%. The Weighted average atomic mass of the element X is closet to _________.

(a)

201 u

(b)

202 u

(c)

199 u

(d)

200 u

Carbon forms two oxides, namely carbon monoxide and carbon dioxide. The equivalent mass of which element remains constant ?

(a)

Carbon

(b)

Oxygen

(c)

Both carbon and oxygen

(d)

Neither carbon nor oxygen

The number of water molecules in a drop of water weighing 0.018 g is ________.

(a)

6.022\(\times\)10²⁶

(b)

6.022\(\times\)10²³

(c)

6.022\(\times\)10²⁰

(d)

9.9 \(\times\)10²²

Fe2 + \(\longrightarrow\) Fe³⁺ + e^- is a ________ reaction.

(a)

redox

(b)

reduction

(c)

oxidation

(d)

decomposition

Which one of the following represents 180 g of water ?

(a)

5 Moles of water

(b)

90 moles of water

(c)

\(\frac { 6.022\times { 10 }^{ 23 } }{ 180 } \) molecules of water 

(d)

6.022\(\times\)10²⁴molecules of water

Total number of electrons present in 1.7 g of ammonia is _____.

(a)

6.022\(\times\)10²³

(b)

\(\frac { 6.022\times { 10 }^{ 22 } }{ 1.7 } \quad \)

(c)

\(\frac { 6.022\times { 10 }^{ 24 } }{ 1.7 } \)

(d)

\(\frac { 6.022\times { 10 }^{ 23 } }{ 1.7 } \)

Consider the following statements :
(i) Oxidation number of He = zero
(ii) Increase in oxidation number results in reduction.
(iii) The substance undergoing the increase in oxidation number is reducing agent.
Which among the above statement(s) is/are correct?

(a)

only (i)

(b)

(ii) and (iii)

(c)

(i) and (iii)

(d)

only (ii)

Identify the correct statement(s) with respect to the following reaction :
Zn + 2HCl \(\longrightarrow\) ZnCl₂ + H₂
(i) Zinc is acting as an oxidant
(ii) Chlorine is acting as a reductant
(iii) Hydrogen is not acting as an oxidant
(iv) Zn is acting as a reductant

(a)

only (ii)

(b)

only (iv)

(c)

both (ii) and (iii)

(d)

both (ii) and (i)

Two 22.4 litre containers A and B contains 8 g of O₂ and 8 g of SO₂ respectively at 273 K and 1 atm pressure, then ______.

(a)

Number of molecules inA and B are same

(b)

Number of molecules in B is more than that in A.

(c)

The ratio between the number of molecules in A= to number of molecules in B is 2:1

(d)

Number of molecules in B is three times greater than the number of molecules in A

Which of the following compound(s) has /have a percentage of carbon same as that in ethylene (C₂H₄)?

(a)

propene

(b)

ethyne

(c)

benzene

(d)

ethane

Maximum oxidation state is present in the central metal atom of which compound

(a)

CrO₂Cl₂

(b)

MnO₂

(c)

[Fe(CN)₆]^3-

(d)

MnO

Consider the following statements
i) Matter possesses mass.
ii) 22-carat gold is a mixture.
iii) Dry ice is a compound.
Which of the following statement(s) given above is/ are correct?

(a)

1 & 3

(b)

Only 1

(c)

1 & 2

(d)

1,2, & 3

The characteristic feature of orderly arrangement of molecules belongs to ______________.

(a)

Solids

(b)

Liquid

(c)

Gases

(d)

None of these

Which form of based on physical characteristics possess neither definite volume nor definite shape?

(a)

Solids

(b)

Liquids

(c)

Gases

(d)

Both (a) and (b)

12 g of carbon-12 contains_____carbon atoms

(a)

6.022\(\times\)10²³

(b)

6

(c)

12

(d)

12.022\(\times\)10^-23 kg

The volume occupied by any gas at S.T.P. is_____ 

(a)

22.4litres

(b)

2.24litres

(c)

224 litres

(d)

0.224 litres

Unit of Avogadro's number is _______________.

(a)

mol

(b)

g

(c)

mol ^-1

(d)

No unit

One 'U' stands for the mass of ______________.

(a)

An atom of carbon-12

(b)

1/12^th of the carbon-12

(c)

1/12th of a hydrogen atom

(d)

One atom of any of the element

In the reaction to NH₃ + H₂O \(\longrightarrow \) \({ NH }_{ 4 }^{ + }+O\overline { H } \), NH₃ is acidic in. the reason for its acidic is_____ 

(a)

Acceptance of one ^H+from water

(b)

A release of one OH^-ion

(c)

Due to the nitrogen atom

(d)

All the above

Assertion: The atomic masses of most of the elements. are in the fraction. 
Reason:  The atomic mass represents the ratio of the average mass of the atom to one avogram.
Codes:
(a) Both assertion and reason are correct and the reason is the correct explanation for assertion
(b) Both assertion and reason are correct but the reason is not the correct explanation for an assertion
(c) Assertion is true but reason are false
(d) Both assertion and reason are false

(a)

Both assertion and reason are correct and the reason is the correct explanation for assertion

(b)

Both assertion and reason are correct but the reason is not the correct explanation for an assertion

(c)

Assertion is true but reason are false

(d)

Both assertion and reason are false