<span>a) 7.9x10^9
b) 1.5x10^9
c) 3.9x10^4
To determine what percentage of an isotope remains after a given length of time, you can use the formula
p = 2^(-x)
where
p = percentage remaining
x = number of half lives expired.
The number of half lives expired is simply
x = t/h
where
x = number of half lives expired
t = time spent
h = length of half life.
So the overall formula becomes
p = 2^(-t/h)
And since we're starting with 1.1x10^10 atoms, we can simply multiply that by the percentage. So, the answers rounding to 2 significant figures are:
a) 1.1x10^10 * 2^(-5/10.5) = 1.1x10^10 * 0.718873349 = 7.9x10^9
b) 1.1x10^10 * 2^(-30/10.5) = 1.1x10^10 * 0.138011189 = 1.5x10^9
c) 1.1x10^10 * 2^(-190/10.5) = 1.1x10^10 * 3.57101x10^-6 = 3.9x10^4</span>
The answer is D but I gotta make this answer 20 characters real quick so ignore what I'm saying ja ja ja the cat go wow the I guess on this and I answer it a but the dog go wolf wolf moo
Answer:
If mass increases, force increases.
Explanation:
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Answer:
Explanation:
1 mol of methane = 6.02 * 10^23 molecules
6.70 mol of methane = x
Cross multiply
x = 6.70 * 6.02 * 10^23
x = 4.033 * 10^23 molecules.
Is a compound that went through a chemicAl change