Explanation:
The scientific notation:
where
and k is integer.
We have the example:
You can write the numbers in a "normal" form:
Make the sum:
And next write it in the scientific notation:
<h3>Other method:</h3>
You can add numbers in scientific notation if the power of tens in both number is the same.
Therefore you must convert the first number:
Now, you can make the sum:
We’ll be using the equation:
dG = dH - TdS (replace ‘d’ with triangle)
I’m going to assume 0 degrees Celsius.
At 0 C (273 K):
dG = dH - TdS
dG = (285,400 J) - (273 K)(-137.14 J/K)
dG = 285,400 J + 37,439.2 J
dG = 322,839.2 J or 322.84 kJ
The dG of this reaction is +322.84 kJ. This reaction is not considered spontaneous.
This answer, in this instance, would be D. If the temperature used in the question is not 0 degrees C, replace the temperature that I used for calculation with the Kelvin temperature given in the problem (K = C + 273), and simplify to find the answer.
