Number #2 is joule
In the SI system the unit of heat is the joule. The calorie was defined so that the heat capacity of water was equal to one.The heat capacity of a substance is the amount of heat required to raise the temperature of a defined amount of pure substances by one degree.
Number #3 is Endothermic
Why? I can't explain. I Just left class where they were just explaining that.
Answer:
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Explanation:
∆H° = ∆Hf ° (products) – ∆Hf ° (reactants)
My guess on that molecule is nucleus , sorry if it’s not correct
answer: its 7290 joules.
explanations: the first procedure is to convert 1 pound to kilogram. 1 kg = 2.205 hence given 100 lb so we cross multiply. 1 kg * 100 = 2.205 * x
hence x= 45 kg. let's convert 1 mile per hour = 0.45 metre per second we cross multiply by 40 mile per hour. x= 40 * 0.45= 18 m/s.
KE= 1/2 * 45 * (18)^2
= 1/2 * 45 * 14580
= 7290joules