I think the answer is C. 02
Ln(800/3200) = - kt
t = 24 years.
ln(0.25) = -k*24
(- 1.3863) = -k*24
1.3863 / 24 = k
0.05776 = k
ln(0.5) = -k*t
-0.6931 = - 0.05776 t
12 = t
I don't know if you can just look at the question and know the answer. If 24 years is a quarter life then is it obvious that the 1/2 life is 12 years? It might be, but the method I've used works for sure.
The answer is 185.87g to 2 decimal places.
Answer:
17.136 g H2
Explanation:
First we need to convert moles of Zinc to moles of Hydrogen in order to find out how many moles of hydrogen are produced.
When we look at our balanced equation, we can see that for every mole of Zn reacting, there is 1 mol of H2 produced. (imagine a 1 in front of the elements that have no numbers in front of them)
8.5 mol Zn *
= 8.5 mol H2
Now we will convert from moles of Hydrogen to grams
The atomic mass of H2 is 2(1.008) g/1 mol... so we will use this to convert to the number of grams of Hydrogen produced..
8.5 mol H2 *
= 17.136 g H2
The first answer is nine you are currently correct