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professor190 [17]
3 years ago
9

223Ra decays by alpha emission with a half-life of 11.43 days. For a 1.0g sample of 223Ra, after one half-life, what mass of 223

Ra remains? What has happened to the remaining mass?
Chemistry
1 answer:
Ray Of Light [21]3 years ago
6 0

Explanation:

The reaction that shows the alpha decay of ^{223}_{88}Ra is:

^{223}_{88}Ra\rightarrow ^{219}_{86}Rn+^{4}_{2}He

Half life is the time at which the concentration of the reactant reduced to half. So,

Mass\ of\ ^{223}_{88}Ra\ remained=\frac {Initial\ concentration}{2}=\frac {1.0\ g}{2}=0.5\ g

The remaining mass is converted to ^{219}_{86}Rn.

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The integrated rate law expression for a first order reaction is

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