1
WB JEE 2018
MCQ (Single Correct Answer)
+1
-0.33
The half-life of C14 is 5760 years. For a 200 mg sample of C14, the time taken to change to 25 mg is
A
11520 years
B
23040 years
C
5760 years
D
17280 years
2
WB JEE 2018
MCQ (Single Correct Answer)
+1
-0.33
The nucleus $$_{29}^{64}$$Cu accepts an orbital electron to yield,
A
$$_{28}^{65}$$Ni
B
$$_{30}^{64}$$Zn
C
$$_{28}^{64}$$Ni
D
$$_{30}^{65}$$Zn
3
WB JEE 2017
MCQ (Single Correct Answer)
+1
-0.25
C6H5F18 is a F18 radio-isotope labelled organic compound. F18 decays by positron emission. The product resulting on decay is
A
C6H5O18
B
C6H5Ar19
C
B12C5H5F
D
C6H5O16
4
WB JEE 2016
MCQ (Single Correct Answer)
+1
-0.25
If radium and chlorine combine to form radium chloride, the compound would be
A
half as radioactive as radium
B
twice as radioactive
C
as radioactive as radium
D
not radioactive
WB JEE Subjects