Answer:
w = -531 kJ
1. Work was done by the system.
Explanation:
Step 1: Given data
- Heat gained by the system (q): 687 kJ (By convention, when the system absorbs heat, q > 0).
- Change in the internal energy of the system (ΔU°): 156 kJ
Step 2: Calculate the work done (w)
We will use the following expression.
ΔU° = q + w
w = ΔU° - q
w = 156 kJ - 687 kJ
w = -531 kJ
By convention, when w < 0, work is done by the system on the surroundings.
<h3>Answer:</h3><h2>Chemical properties</h2><h3>Explanation:</h3>
By its very definition, a chemical property is one which is exhibited as a result of a chemical reaction. This may happen during or after the reaction. This is because in a chemical reaction there is a transformation in the physical composition of the components and this directly affects its chemical properties.
Answer: The actual reaction to make water is a bit more complicated: 2H2 + O2 = 2H2O + Energy. In English, the equation says: To produce two molecules of water (H2O), two molecules of diatomic hydrogen (H2) must be combined with one molecule of diatomic oxygen (O2). Energy will be released in the process.
Explanation:
A. Intermediate is the answer
It is true that enzymes speed up the reaction by lowering the activation energy. However, the main concept here is the compatibility of an enzyme to its substrate. This is achieved through lock-and-key theory or the induced fit theory. Either way, the enzymes manipulate the substrates near to the amino acids that can transfer protons (hydrogen ions). This is how it speeds up the reaction.