Which of the following lists contains ONLY unstable isotopes?
(A) $^{207}_{82}Pb$, $^{99}_{43}Tc$, $^{12}_{7}N$
(B) $^{214}_{82}Pb$, $^{46}_{20}Ca$, $^{99}_{43}Tc$
(C) $^{238}_{92}U$, $^{12}_{7}N$, $^{40}_{20}Ca$
(D) $^{238}_{92}U$, $^{99}_{43}Tc$ - HSC - SSCE Chemistry - Question 7 - 2011 - Paper 1
Question 7
Which of the following lists contains ONLY unstable isotopes?
(A) $^{207}_{82}Pb$, $^{99}_{43}Tc$, $^{12}_{7}N$
(B) $^{214}_{82}Pb$, $^{46}_{20}Ca$, $^{99}_{43}Tc$... show full transcript
Worked Solution & Example Answer:Which of the following lists contains ONLY unstable isotopes?
(A) $^{207}_{82}Pb$, $^{99}_{43}Tc$, $^{12}_{7}N$
(B) $^{214}_{82}Pb$, $^{46}_{20}Ca$, $^{99}_{43}Tc$
(C) $^{238}_{92}U$, $^{12}_{7}N$, $^{40}_{20}Ca$
(D) $^{238}_{92}U$, $^{99}_{43}Tc$ - HSC - SSCE Chemistry - Question 7 - 2011 - Paper 1
Step 1
Identify the isotopes in option (A)
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
82207Pb is stable; 4399Tc is unstable; 712N is unstable.
Step 2
Identify the isotopes in option (B)
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
82214Pb is unstable; 2046Ca is stable; 4399Tc is unstable.
Step 3
Identify the isotopes in option (C)
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
92238U is unstable; 712N is unstable; 2040Ca is stable.
Step 4
Identify the isotopes in option (D)
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
92238U is unstable; 4399Tc is unstable.
Step 5
Conclusion
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Only option (B) contains solely unstable isotopes: 82214Pb and 4399Tc.
