The unit cm3 is used to express a cube using cm
Anions are negative ions so it’s when an atom gains electrons
I think it is B silicon and iron.
The time the chocolate bar could power the laptop in hours is 0.00233 hrs.
Since 200 Calories of chocolate bar were burned to power the 100 Watt laptop, we need to find the number of joules on energy in 200 calories of chocolate bar.
Knowing that 4.2 Joules = 1 Calorie, then
200 Calories = 200 × 1 calorie = 200 × 4.2 Joules = 840 Joules
Since the power required by the laptop is 100 W = 100 J/s and Power, P = energy/time
so, time = energy/power
So, the time for the laptop to use 840 J of energy from the chocolate bar at a rate or power of 100 W = 100 J/s is
time = 840 J ÷ 100 J/s = 8.4 s
So, the time in hours is 8.4 s ÷ 3600 s/1 h = 0.00233 hrs (since 1 hr = 3600 s)
So, the time the chocolate bar could power the laptop in hours is 0.00233 hrs.
Learn more about time to power here:
brainly.com/question/17732603
Answer: Option (c) is the correct answer.
Explanation:
It is known that when Gibb's free energy, that is, 
has a negative value then the reaction will be spontaneous and the formation of products is favored more rapidly.
Activation energy is defined as the minimum amount of energy required to initiate a chemical reaction.
So, when reactants of a chemical reaction are unable to reach towards its activation energy then a catalyst is added to lower the activation energy barrier so the reaction can take place rapidly.
Since, the given reaction has low activation energy. Therefore, there is no need to add a catalyst.
And, when value of is positive then the reaction is spontaneous in nature and formation of products is less favored.
Thus, we can conclude that for the given situation positive delta G is the reason that a reaction might form products very slowly, or not at all.
