From the calculations, the half life of the material is 6.5 days.
<h3>What is radioactivity?</h3>
The term radioactivity has to do with the spontaneous disintegration of a specie.
Uisng the formula;
N=Noe^-kt
N= amount at time t = 0.135 Ci or 4.995 ×10^9 Bq
No = amount initially present = 1.75 x 10^12 Bq
k = rate constant = ?
t = time taken = 55 days
Hence;
4.995 ×10^9 = 1.75 x 10^12e^-55k
4.995 ×10^9/1.75 x 10^12 = e^-55k
2.85 * 10^-3 = e^-55k
ln2.85 * 10^-3 = -55k
k = ln2.85 * 10^-3/-55
k = 0.1066 day-1
Half life = 0.693/ 0.1066 day-1
= 6.5 days
Learn more about radioactivity:brainly.com/question/1770619
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Answer:
1.586x10^-9
Explanation:
To make a multiplication in scientific notation we need to multiply the coefficients and sum the exponents:
Coefficients: 2.600 * 6.1000 = 15.86
Exponents: -5 + (-5) = -10
The result is:
15.86x10^-10
As the scientific notation must be given with only 1 number in the left of the point:
<h3>1.586x10^-9</h3>
Answer:
The answer is
<h2>0.89 atm </h2>
Explanation:
To convert from kPa to atm we use the conversion
101.325 kPa = 1 atm
If
101.325 kPa = 1 atm
Then
90.23 kPa will be
We have the final answer as
<h3>0.89 atm</h3>
Hope this helps you
The answer is
<span>2PbS(s) + 3O2(g) = 2PbO(s) + 2SO2(g)
Your answer is not yet balanced because you have 3 oxygen atoms. it should be balanced by multiplying both side by 2 such as the balanced equation I made. To check it, I will explain why your answer is not yet balanced.
check: (from your equation)
</span> 1-Pb-1
1-S-1
2 -O-3
the difference between the reactant and the product of Oxygen will prove that it is not yet balanced.
If you use 2PbS(s) + 3O2(g) = 2PbO(s) + 2SO2(g), to check it:
2-Pb-2
2-S-2
6 -O-6
then this is now balance
