Nothing in particular determines the name of an element, it could range from who discovered it to where it was discovered!
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.
The time taken by Carbon-14 to decay radioactively from 120g to 112.5g is 22,920 years.
<h3>How do we calculate the total time of decay?</h3>
Time required for the whole radioactive decay of any substance will be calculated by using the below link:
T = (n)(t), where
- t = half life time = 5730 years
- n = number of half life required for the decay
Initial mass of Carbon-14 = 120g
Final mass of Carbon-14 = 112.5g
Left mass = 120 - 112 = 7.5g
Number of required half life for this will be:
- 1: 120 → 60
- 2: 60 → 30
- 3: 30 → 15
- 4: 15 → 7.5
4 half lives are required, now on putting values we get
T = (4)(5730) = 22,920 years
Hence required time for the decay is 22,920 years.
To know more about radioactive decay, visit the below link:
brainly.com/question/24115447
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The answer is D. Heterogeneous mixture
Answer: Option (a) is the correct answer.
Explanation:
A protein part of an enzyme is known as an apoenzyme. An apoenzyme combines with a cofactor, it is known as holoenzyme.
Without a cofactor an apoenzyme cannot function as cofactor helps in the formation of an active enzyme system and provides a specific site on enzyme for the substrate.
Whereas a non-protein chemical compound or metal ion that helps in the activity of enzyme as a catalyst is known as a cofactor. A metal ion cofactor can be bound directly to the enzyme or to a coenzyme.
The organic non-protein molecules which bind to the protein molecule to form an active enzyme is known as a coenzyme. Coenzymes are small size molecules which help the enzymes to act as a catalyst.
Therefore, we can conclude that the statement an apoenzyme can catalyze its reaction without its cofactor, is false.
