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lbvjy [14]
2 years ago
11

PLEASE!!! I NEED HELP ASAP!!

Chemistry
2 answers:
Lana71 [14]2 years ago
7 0
W=m₁/m₀=2^(-t/T)

t=4.6·10⁹ years
T=5·10¹⁰ years

w=2^(-4.6·10⁹/5·10¹⁰)

w=0.9382
w=93.82%

iris [78.8K]2 years ago
5 0

Answer:

the ratio of parent to daughter =  15.38 : 1

Explanation:

The radioactive disintegration is considered to be first order reaction.

The relation between first order rate constant and the half life is:

k=\frac{0.693}{t_{\frac{1}{2} }}

Let us calculate the rate constant from half life as

k=\frac{0.693}{50}=0.01386 (billionyr)^{-1}

The rate law expression for first order reaction is

kt=ln\frac{[A0]}{At}

Where

A0 = initial amount of rubidium isotope = say 100

At= final amount of rubidium isotope after 4.6 billion years

putting all values

0.1386X4.6=ln\frac{100}{At}

1.065=100/At

At=93.897

The amount of daughter isotope formed =100-93.897 = 6.103

the ratio of parent to daughter = 93.897:6.103 = 15.38 : 1

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