Answer:

Explanation:
At constant pressure Thermal energy always moves from a greater energy level to a lesser energy level, laws of thermodynamics prove that.
Nature always likes to attain equilibrium either it's movement of heat energy or flow of water from higher region to lower region. The first and second law of thermodynamics are profe of that, the first law says that the total energy of universe is Constant. Energy can not be destroyed it always changes from one form to another, by work and heat. The second law explains why thermal energy moves from a greater energy level to a lesser energy level, it deals with the change in entropy of a system and surrounding and states heat flows from hot environment to cold environment.
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Hydrogen + oxygen --> water
2,1g + 16,8g = x
x = 18,9g
Fossil fuels and unnatural energy sources still dominate in the US, this influences many problems including global warming, climate change, and pollution. Burning fossil fuels is also a problem to human health. And unnatural resources won’t be there forever whereas, renewable sources could last a long time.
Condensation<span> is the process by which </span>water<span> vapor in the air is changed into liquid </span>water<span>. </span>Condensation<span> is crucial to the </span>water cycle<span> because it is responsible for the formation of clouds. ... </span>Condensation<span> is the opposite of evaporation.</span>