Answer:
B. A chemical change occurred which caused the liquid's physical properties to change.
Explanation:
The reduction of the temperature of the system meant that the reaction absorbed heat energy from it. This shows that a chemical reaction was in progress. New products were formed, and this is proved by the change in the color to blue.
Answer:
concrete
2kj for second question
Explanation:
it's gotta be because... let me get back on it.
<u>Given:</u>
Mass = 68 kg
Power = 65 W
<u>To determine:</u>
Calories burned during an 8.0 hr sleep
<u>Explanation:</u>
Energy is expressed as:
Energy = Power * Time
Now, the unit of power = Watt (W)
1 W = 1 J/s i.e. 65 W = 65 J/s
Time = 8 hrs = 8 * 3600 s = 28800 s
Energy = 65 J/s * 28800 s = 1872000 J
Convert Joules (J) to calories (cal)
1 cal = 4.184 J
The calculated energy = 187200 J * 1 cal/4.184 = 447418 cal
Ans: The man burns nearly 447.4 kcal during an 8 hr sleep
Answer:
1. Options A and B
2. Options B and C
3.. B. Net ∆G = -16.7 KJ/mol; C. Net ∆G = -14.2 KJ/mol
Explanation:
1. The spontaneity of a chemical reaction depends on its standard free energy change, ∆G. If ∆G is negative, the reaction is favourable, but when it is positive, the reaction is unfavorable.
Therefore, since reaction A and B have ∆G to be positive, they are unfavorable
2. Coupling an unfavorable reaction to a favourable reaction can help the reaction to proceed in the forward direction as long as the net free energy change is negative.
Coupling reaction A and C, as well as reaction B and C will make the reactions to become favourable as net ∆G is negative in both instances.
3. A and C: net ∆G = 13.8 - 30.5 = -16.7 KJ/mol
B and C: net ∆G = 16.3- 30.5 = -14.2 KJ/mol
Answer:
the first on is Chromium(VI) peroxide or chromium oxide peroxide
the second on it Hydrogen Carbonate
Explanation:
I hope this helped ;)
