The isotopes of promethium, and are unstable, and lie on opposite sides of the "line of stability". Which of the following combinations is most likely to represent the type of decay for these isotopes?
A) promethium-144, $\beta$ decay; promethium-134, positron decay
B) promethium-144, positron decay; promethium-134, $\beta$ decay
C) promethium-144, positron decay; promethium-134, electron capture
D) promethium-144, electron capture; promethium-134, positron decay
E) promethium-144, $\beta$ decay; promethium-134, $\gamma$ decay

Question

The isotopes of promethium,  and  are unstable, and lie on opposite sides of the "line of stability". Which of the following combinations is most likely to represent the type of decay for these isotopes?
A) promethium-144, $\beta$ decay; promethium-134, positron decay 
B) promethium-144, positron decay; promethium-134, $\beta$ decay 
C) promethium-144, positron decay; promethium-134, electron capture 
D) promethium-144, electron capture; promethium-134, positron decay 
E) promethium-144, $\beta$ decay; promethium-134, $\gamma$ decay

Quizplus · Accepted Answer

The Answer of The isotopes of promethium,  and  are unstable, and lie on opposite sides of the "line of stability". Which of the following combinations is most likely to represent the type of decay for these isotopes?
A) promethium-144, $\beta$ decay; promethium-134, positron decay 
B) promethium-144, positron decay; promethium-134, $\beta$ decay 
C) promethium-144, positron decay; promethium-134, electron capture 
D) promethium-144, electron capture; promethium-134, positron decay 
E) promethium-144, $\beta$ decay; promethium-134, $\gamma$ decay

The Isotopes of Promethium, and Are Unstable, and Lie