M (C2H6) = n × M = 4.6 × 30 = 13.8 g.
T is amount after time t
<span>Ao is initial amount </span>
<span>t is time </span>
<span>HL is half life </span>
<span>log (At) = log [ Ao x (1/2)^(t/HL) ] </span>
<span>log (At) = log Ao + log (1/2)^(t/HL) </span>
<span>log (At) = log Ao + (t/HL) x log (1/2) </span>
<span>( log At - log Ao) / log (1/2) = t / HL </span>
<span>log (At/Ao) / log (1/2) = t / HL </span>
<span>HL = t / [( log (At / Ao)) / log (1/2) ] </span>
<span>HL = 14.4 s / [ ( log (12.5 / 50) / log (1/2) ] </span>
<span>HL = 14.4 s / 2 = 7.2 seconds </span>
Answer:
atoms of hydrogen
Explanation:
The molecular formula for a water molecule is 
.
From the above formula, we can conclude that 1 molecule of water contains 2 atoms of hydrogen and 1 atom of oxygen.
There are 
molecules of water.
1 molecule of water = 2 atoms of hydrogen.
∴ molecules of water = 
atoms of hydrogen.
Therefore, there are atoms of hydrogen in molecules of water.
A molecule consisting of 100 amino acids has a molar mass
of 10,000 amu. The answer is letter A.
The role of the enzyme is to speed up biochemical
reactions. The answer is letter A. it does not take part in the reaction.
<span>19. Single displacement reactions are always redox reactions (they include reaction between an element and a compound where they will take place of another element in that compound).
20. It should be single displacement, where the displaced ion would form gas.</span>
