18
MCQ (Single Correct Answer)
Only one element of ........... forms hydride.
A
group 6
B
group 7
C
group 8
D
group 9
19
MCQ (Multiple Correct Answer)
Which of the following statements are not true for hydrogen?
A
It exists as diatomic molecule
B
It has one electron in the outermost shell
C
It can lose an electron to form a cation which can freely exist
D
It forms a large number of ionic compounds by losing an electron
20
MCQ (Multiple Correct Answer)
Dihydrogen can be prepared on commercial scale by different methods. In its preparation by the action of steam on hydrocarbons, a mixture of CO and $\mathrm{H}_2$ gas is formed. It is known as ........... .
A
water gas
B
syn gas
C
producer gas
D
industrial gas
21
MCQ (Multiple Correct Answer)
Which of the following statement(s) is/are correct in the case of heavy water?
A
Heavy water is used as a moderator in nuclear reactor
B
Heavy water is more effective as solvent than ordinary water
C
Heavy water is more associated than ordinary water
D
Heavy water has lower boiling point than ordinary water
22
MCQ (Multiple Correct Answer)
Which of the following statements about hydrogen are correct?
A
Hydrogen has three isotopes of which protium is the most common
B
Hydrogen never acts as cation in ionic salts
C
Hydrogen ion, $\mathrm{H}^{+}$, exists freely in solution
D
Dihydrogen does not act as a reducing agent