Abundance and Isotopes

Q. How many oxygen atoms are present in 2 gram-atoms of $O$?

1. $12.044\times {10}^{23}$
2. $2.26\times {10}^{23}$
3. $6.022\times {10}^{23}$
4. $3.011\times {10}^{23}$

Q. At absolute zero temperature:

1. Only para hydrogen exists
2. Only ortho hydrogen exist
3. Both para and ortho hydrogen exist
4. None

Q. Which of the following has high melting point?

1. $H_2$
2. $D_2$
3. $T_2$
4. Both A and B

Q. Ordinary hydrogen at room temperature is a mixture of:

1. 75% orthohydrogen + 25% parahydrogen
2. 25% orthohydrogen + 75% parahydrogen
3. 1% orthohydrogen + 99% parahydrogen
4. 50% orthohydrogen + 50% parahydrogen

Q. Choose the correct statement with respect to ortho hydrogen:
Statement-I: In ortho hydrogen, the spin of both nuclei are in same direction.
Statement-II: Ortho hydrogen is more abundant than para hydrogen at room temperature.
Statement-III: Thermal conductivity of ortho hydrogen is more than para hydrogen.

1. I, III
2. I, II
3. II, III
4. I, II, III

Q. Which of the following is true about the spin-isomers of hydrogen?

1. Ortho hydrogen has same spins of two nuclei clockwise or anti-clockwise
2. Para hydrogen has different spins of two nuclei
3. At about absolute zero, there is 100% para form and at higher temperature, there is 75% ortho form
4. All are correct

Q. In a hydrogen molecule, when the spins are in the same direction. What is it known as?

1. adsorbent hydrogen
2. nascent hydrogen
3. para hydrogen
4. ortho hydrogen

Q. Tritium, a radioactive element on decay forms an isotope of an inert gas and emits a beta particle. The inert gas is

1. Helium
2. Argon
3. Neon

Q. In nuclear transmutation Tritium is obtained from

1. $N_7^{14}$
2. $C_7^{14}$
3. $L{i}_3^6$
4. $O_8^{16}$

Q.

Name an isotope of hydrogen which

i) has same number of protons and neutrons.

ii) is most abundant on earth.

Q.

Which isotope of hydrogen is most abundant in nature?

Q.

What is common for H+, D+ and T+

1. No of electrons

2. No of protons

3. No of neutrons

4. Activation energy

Q.

Nuclear spin isomerism is exhibited by

1. Hydrogen molecule

2. Deuterium molecule

3. Tritium molecule

4. All of the above

Q. Orthohydrogen and parahydrogen have

1. Same nuclear spin, different physical and chemical properties
2. Same nuclear spin with identical physical and chemical properties
3. Different nuclear spin with differences in physical and chemical properties
4. Different nuclear spin and with different physical properties

Q. The most abundant isotope of hydrogen is

1. Tritium
2. Deuterium
3. Protium
4. Para hydrogen