Question 1: Palette 1/8

NEET 2022 MCQ

The half life of a first order reaction is 2000 years. If the concentration after 8000 years is 0.02 M, then the initial concentration was :

A

0.04 M

B

0.16 M

C

0.32 M

D

0.08 M

Question 2: Palette 2/8

NEET 2005 MCQ

A nuclide of an alkaline earth metal undergoes radioactive decay by emission of the periodic table to which the resulting daughter element would belong is

A

Gr.13

B

Gr. 17

C

Gr. 14

D

Gr. 16

Question 3: Palette 3/8

NEET 2004 MCQ

The radioactive isotope ${}_{27}^{60}$Co which is used in the treatment of cancer can be made by (n.p) reaction. For this reaction the tarfet nucleus is

A

$_{28}^{59}$ Ni

B

$_{27}^{59}$ Co

C

$_{28}^{60}$ Ni

D

$_{27}^{60}$ Co

Question 4: Palette 4/8

NEET 2003 MCQ

The radioistope, tritium (${}_1^3$H) has a half-life of 12.3 years. If the initial amount of tritium is 32 mg, how many milligrams of it would remain after 49.2 years?

A

1 mg

B

2 mg

C

4 mg

D

8 mg

Question 5: Palette 5/8

NEET 2002 MCQ

${}_{92}^{235}$U, nucleus absorbs a neutron and distintegrate in ${}_{54}^{139}$Xe, ${}_{38}^{94}$Sr and $x$ so, what will be product $x$?

A

3-neutrons

B

2-neutrons

C

$\alpha $-particle

D

$\beta $-particle

Question 6: Palette 6/8

NEET 2001 MCQ

A human body required 0.01 m activity of radioactive substance after 24 hours. Half life of radioactive substance is 6 hours. Then inhection of maximum activity of radioactive substance that can be injected is

A

0.08

B

0.04

C

0.16

D

0.32

Question 7: Palette 7/8

NEET 2001 MCQ

If a ${}_b^aX$ species emits first a position, then two a and two b particles and in the last, one a, is also emitted and gets converts to ${}_d^c$Y species. So correct relation is

A

c = a $-$ 12, d = b $-$ 5

B

c = a $-$ 5, d = b $-$ 1

C

c = a $-$ 6, d = b $-$ 0

D

c = a $-$ 4, d = b $-$ 2

Question 8: Palette 8/8

NEET 2000 MCQ

A 300 grams radioactive sample at initial half life is 3 hours. After 18 hours remaining quantity

A

4.68 gram

B

2.34 gram

C

3.34 gram

D

9.37 gram