PCTB 1st Year Chemistry — MCQs, Short & Long Questions

Which of the following statements is true?

a
Isotopes with odd atomic number are comparatively abundant
b
Isotopes with odd atomic masses are comparatively abundant
c
Isotopes with even atomic masses are comparatively abundant
d
Isotopes with odd odd atomic masses are comparatively abundant

Many elements have fractional atomic masses. This is because:

a
Tha mass of the atom is itself fractional
b
Atomic masses are average masses of isobars
c
Atomic masses are average masses of isotopes
d
Atomic masses are average masses of isotopes proportional to their relative abundance

The mass of one mole of electron is:

a
1.008 mg
b
0.55 mg
c
0.148 mg
d
1.673 mg

27g of Al will react completely with how much mass of

\textup O_{2}

to produce

\textup {A l}_{2} \textup O_{3}

a
8 g of oxygen
b
16 g of oxygen
c
32 g of oxygen
d
24 g of oxygen

The number of moles of

\textup {C O}_{2}

which contain 8.0g of oxygen:

a
0.25
b
0.50
c
1.0
d
1.50

The largest number of molecules are present in:

a
3.6 g of $\textup H_{2} \textup O$
b
4.8 g of $\textup C_{2} \textup H_{5} \textup O H$
c
2.8 g of $\textup {C O}_{} \textup_{} \textup$
d
5.40g of $\textup N_{2} \textup O_{5} \textup$

One mole of

\textup {S O}_{2} \textup_{} \textup

contains:

a
$6.02 \times 10^{23} \textup {a t o m s o f o x y g e n}_{} \textup_{} \textup$
b
$18.1 \times 10^{23} \textup {m o l e c u l e s o f S O}_{2} \textup_{} \textup$
c
$6.02 \times 10^{23} \textup {a t o m s o f S u l p h u r}_{} \textup_{} \textup$
d
$\textup {4 g r a m s a t o m s o f S O}_{2} \textup_{} \textup$

The volume occupied by 1.4 g of

\textup N_{2} \textup_{} \textup

at S.T.P is:

a
$\textup {2.24 d m}^{2} \textup_{} \textup$
b
$\textup {22.4 d m}^{2} \textup_{} \textup$
c
$\textup {1.12 d m}^{2} \textup_{} \textup$
d
$\textup {112cm}^{} \textup_{} \textup$

A limiting reactant is the one which:

a
Is taken in lesser quantity in grams as compared to other reactants
b
Is taken in lesser quantity in volume as compared to the other reactants
c
Gives maximum amount of the product which is required
d
Gives the minimum amount of the product under consideration

Isotopes differ in:

a
Properties which depends upon mass
b
Arrangement of electrons in orbitals
c
Chemical properties
d
The extent to which they may be affected in electromagnetic

One amu is equal to:

a
$1.661 \times 10^{27} \textup {k g}_{} \textup_{}$
b
$1.661 \times 10^{- 27} \textup {k g}_{} \textup_{}$
c
$1.661 \times 10^{- 24} \textup {k g}_{} \textup_{}$
d
$1.661 \times 10^{- 27} \textup g_{} \textup_{}$

Tin has isotopes:

a
7
b
9
c
11
d
5

The mass of one mole of electron is:

a
1.008 mg
b
0.55 mg
c
0.184 mg
d
1.673 mg

the number of moles of

\textup {C O}_{2} \textup_{}

which contains 8.0 g of oxygen is:

a
0.25
b
0.50
c
1.0
d
1.50

How many isotopes are present in palladium?

a
Four
b
Five
c
Six
d
Seven

27 g of Al will react completely with how much of

\textup O_{2} \textup_{}

to produce

\textup {A l}_{2} \textup O_{3}

a
8 g of oxygen
b
16 g of oxygen
c
32 g of oxygen
d
24 g of oxygen

The volume occupied by 1.4 g of N₂ at STP is:

a
$2.24 \textup {d m}^{3} \textup_{}$
b
$22.4 \textup {d m}^{3} \textup_{}$
c
$1.12 \textup {d m}^{3} \textup_{}$
d
$112 \textup {c m}^{3} \textup_{}$

One mole of

\textup {S O}_{2} \textup_{}

contains:

a
$6.02 \times 10^{23} \textup {a t o m s o f o x y g e n}_{} \textup_{}$
b
$18.1 \times 10^{23} \textup {m o l e c u l e s o f}_{} \textup {S O}_{2}$
c
$6.02 \times 10^{23} \textup {a t o m s o f s u l p h u r}_{} \textup_{}$
d
$\textup {4 g a t o m s o f S O}_{2} \textup_{}$

J.Berzelius determined the:

a
Atomic mass
b
Atomic numbers
c
Isotopes
d
Relative abundance

The number of carbon atoms in 22.0 g of

\textup {C O}_{2} \textup_{}

is:

a
$3.01 \times 10^{23} \textup_{} \textup_{}$
b
$6.022 \times 10^{23} \textup_{} \textup_{}$
c
$3.01 \times 10^{22} \textup_{} \textup_{}$
d
$3.02 \times 10^{22} \textup_{} \textup_{}$

Chemistry

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