Major Competitive Exams
Q. Which of the following measures is NOT a measure of dispersion?
A.
Range
B.
Variance
C.
Mean
D.
Standard Deviation
Show solution
Solution
Mean is a measure of central tendency, not dispersion.
Correct Answer: C — Mean
Learn More →
Q. Which of the following measures of dispersion is affected by extreme values?
A.
Range
B.
Interquartile Range
C.
Variance
D.
Standard Deviation
Show solution
Solution
Range is affected by extreme values as it is calculated as the difference between the maximum and minimum values.
Correct Answer: A — Range
Learn More →
Q. Which of the following metals can be used as an anode in a Daniell cell?
A.
Copper
B.
Zinc
C.
Silver
D.
Lead
Show solution
Solution
Zinc is used as the anode in a Daniell cell.
Correct Answer: B — Zinc
Learn More →
Q. Which of the following metals can be used as an anode in electrolysis?
A.
Copper
B.
Gold
C.
Aluminum
D.
Silver
Show solution
Solution
Aluminum is commonly used as an anode in electrolysis due to its high reactivity.
Correct Answer: C — Aluminum
Learn More →
Q. Which of the following metals cannot be used as an anode in a galvanic cell?
A.
Zinc
B.
Copper
C.
Lead
D.
Silver
Show solution
Solution
Copper cannot be used as an anode in a galvanic cell because it is less reactive than zinc.
Correct Answer: B — Copper
Learn More →
Q. Which of the following molecular orbitals is filled first according to the Aufbau principle?
A.
σ1s
B.
σ*1s
C.
π2p
D.
σ2p
Show solution
Solution
According to the Aufbau principle, the σ1s molecular orbital is filled first as it has the lowest energy.
Correct Answer: A — σ1s
Learn More →
Q. Which of the following molecular orbitals is lower in energy than the 2p atomic orbitals?
A.
σ2s
B.
σ*2s
C.
π2p
D.
σ2p
Show solution
Solution
σ2s is lower in energy than the 2p atomic orbitals.
Correct Answer: A — σ2s
Learn More →
Q. Which of the following molecules exhibits resonance?
A.
H2O
B.
CO2
C.
O3
D.
CH4
Show solution
Solution
Ozone (O3) exhibits resonance due to the delocalization of electrons.
Correct Answer: C — O3
Learn More →
Q. Which of the following molecules has a bent shape according to VSEPR theory?
A.
CO2
B.
H2O
C.
NH3
D.
CH4
Show solution
Solution
H2O has two bonding pairs and two lone pairs, leading to a bent molecular geometry.
Correct Answer: B — H2O
Learn More →
Q. Which of the following molecules has a bent shape?
A.
CO2
B.
H2O
C.
NH3
D.
CH4
Show solution
Solution
H2O has two bonding pairs and two lone pairs, leading to a bent molecular geometry.
Correct Answer: B — H2O
Learn More →
Q. Which of the following molecules has a bond order of 1?
A.
H2
B.
He2
C.
Li2
D.
B2
Show solution
Solution
Li2 has a bond order of 1, calculated as (2 bonding electrons - 0 antibonding electrons)/2 = 1.
Correct Answer: C — Li2
Learn More →
Q. Which of the following molecules has a bond order of 2?
Show solution
Solution
N2 has a bond order of 2, calculated as (number of bonding electrons - number of antibonding electrons)/2 = (10-6)/2 = 2.
Correct Answer: B — N2
Learn More →
Q. Which of the following molecules has a higher bond order than N2?
Show solution
Solution
O2 has a bond order of 2, while N2 has a bond order of 3, so none have a higher bond order than N2.
Correct Answer: A — O2
Learn More →
Q. Which of the following molecules has a higher bond order: N2 or O2?
A.
N2
B.
O2
C.
Both are equal
D.
Cannot be determined
Show solution
Solution
N2 has a bond order of 3, while O2 has a bond order of 2, so N2 has a higher bond order.
Correct Answer: A — N2
Learn More →
Q. Which of the following molecules has a linear shape?
A.
CH4
B.
H2O
C.
CO2
D.
NH3
Show solution
Solution
CO2 has a linear shape due to the arrangement of its double bonds.
Correct Answer: C — CO2
Learn More →
Q. Which of the following molecules has a polar covalent bond? (2023)
A.
Cl2
B.
H2O
C.
CH4
D.
O2
Show solution
Solution
Water (H2O) has a polar covalent bond due to the difference in electronegativity between hydrogen and oxygen.
Correct Answer: B — H2O
Learn More →
Q. Which of the following molecules has a polar covalent bond? (2023) 2023
A.
Cl2
B.
H2O
C.
CH4
D.
O2
Show solution
Solution
Water (H2O) has a polar covalent bond due to the difference in electronegativity between hydrogen and oxygen.
Correct Answer: B — H2O
Learn More →
Q. Which of the following molecules has a trigonal bipyramidal geometry?
A.
NH3
B.
PCl5
C.
H2O
D.
CO2
Show solution
Solution
PCl5 has five bonding pairs and no lone pairs, leading to a trigonal bipyramidal geometry.
Correct Answer: B — PCl5
Learn More →
Q. Which of the following molecules has a triple bond?
Show solution
Solution
N2 has a triple bond, consisting of one sigma bond and two pi bonds.
Correct Answer: A — N2
Learn More →
Q. Which of the following molecules has the highest bond order?
Show solution
Solution
N2 has the highest bond order of 3, calculated as (10 bonding electrons - 2 antibonding electrons)/2 = 3.
Correct Answer: A — N2
Learn More →
Q. Which of the following molecules is diamagnetic?
Show solution
Solution
F2 is diamagnetic as it has all electrons paired in its molecular orbitals.
Correct Answer: C — F2
Learn More →
Q. Which of the following molecules is isoelectronic with N2?
Show solution
Solution
C2 is isoelectronic with N2, both having 10 electrons.
Correct Answer: B — C2
Learn More →
Q. Which of the following molecules is isoelectronic with Ne?
Show solution
Solution
N2 is isoelectronic with Ne, both having 10 electrons.
Correct Answer: C — N2
Learn More →
Q. Which of the following molecules is polar?
A.
CCl4
B.
CO2
C.
NH3
D.
CH4
Show solution
Solution
Ammonia (NH3) is polar due to its trigonal pyramidal shape and the presence of a lone pair on nitrogen.
Correct Answer: C — NH3
Learn More →
Q. Which of the following molecules is predicted to be stable according to molecular orbital theory?
A.
He2
B.
Li2
C.
Be2
D.
B2
Show solution
Solution
Li2 is stable with a bond order of 1, while He2 and Be2 are not stable.
Correct Answer: B — Li2
Learn More →
Q. Which of the following numbers has 4 significant figures?
A.
0.0025
B.
2500
C.
25.00
D.
0.02500
Show solution
Solution
25.00 has 4 significant figures due to the trailing zeros after the decimal.
Correct Answer: C — 25.00
Learn More →
Q. Which of the following numbers has the least number of significant figures?
A.
0.00345
B.
12.30
C.
100
D.
0.0456
Show solution
Solution
The number 100 has only 1 significant figure unless specified otherwise.
Correct Answer: C — 100
Learn More →
Q. Which of the following numbers has the least significant figures?
A.
0.00560
B.
0.0560
C.
0.560
D.
5.60
Show solution
Solution
0.00560 has 3 significant figures, 0.0560 has 3 significant figures, 0.560 has 3 significant figures, and 5.60 has 3 significant figures. However, 0.00560 is the smallest number, but all have the same count of significant figures.
Correct Answer: A — 0.00560
Learn More →
Q. Which of the following numbers has the most significant figures?
A.
0.00789
B.
7890
C.
7.890 x 10^3
D.
0.07890
Show solution
Solution
7.890 x 10^3 has 4 significant figures, while the others have 3, 3, and 4 respectively, but the leading zeros in the first and last options do not count.
Correct Answer: C — 7.890 x 10^3
Learn More →
Q. Which of the following numbers has three significant figures?
A.
0.00456
B.
123.4
C.
1001
D.
0.0300
Show solution
Solution
0.0300 has three significant figures (the zeros after the 3 are significant because they come after a decimal point).
Correct Answer: D — 0.0300
Learn More →
Showing 11281 to 11310 of 11933 (398 Pages)