Answer:a) ∆E=-0.077KJ (exothermic)
b) ∆E = 110KJ (endothermic)
Explanation:
a) ∆E = q + w
q= 0.763 KJ
w= -840J = -0.840 KJ
∆E = 0.763-0.840 = - 0.077KJ
Exothermic reaction are those reactions that proceeds with the release of heat to the surroundings and Energy is negative in exothermic processes.
b)/∆E = q+w
q= 66.1KJ, w=44KJ
∆E = 101KJ
And it is endothermic
When work is done on a system, the international energy increases.
<h2><u>My </u><u>Answer</u><u> </u></h2>
<h2>
My Explanation</h2>
Although caffeine (a stimulant found in coffee and tea) is a relatively complicated molecule, it's only eight atoms of carbon, ten of hydrogen, four of nitrogen and two of oxygen – C8H10N4O2. This kind of representation is called a molecular formula – it tells us what kind of atoms we have, and how many of each.
<h2>#CarryOnLearning</h2>
<span>3400 years.
The first thing to do is determine how many half lives the sample has undergone. Assuming that the level of atmospheric carbon 14 has remained consistent over time, the sample has only 2/3rd of the level of activity, so only has 2/3rds of the carbon-14 level. So calculate the logarithm to base 2 of 2/3.
log(2/3)/log(2) = -0.17609/0.30103 = -0.58496
This indicates that 0.58496 half lives have expired which is a reasonable number since if 1 half-life had been spent, the level of activity would be half of modern activity. So just multiply the number of half-lives by the half-life. So
-0.58496 * 5730 = -3351.835129
Rounding to 2 significant figures gives an estimated age of 3400 years.</span>
Answer:
It is the site where oxygen combines with small molecules of glucose and releases large amounts of energy
Explanation:
Balance the equation to find the answer. The easiest place to start is with the C’s and H’s since they only appear once on both sides of the equation:
C4H8 + 6O2 —> 4CO2 + 4H2O
The O2 has already been balanced for us (but normally you would add the number of O’s on the right after balancing C’s and H’s and use that to balance the O’s on the left).
As you can see you get 4 molecules of CO2 and 4 of H2O.