The answer is to this question is c
Answer : The correct option is (C) : Dew forms on grass when water vapor forms when molecules cool and join together.
Explanation :
Air contains a small amount of water vapors. When the temperature of an object is lowered than the ambient temperature, the vapors get condensed and small water droplets are formed on the object.
During night time, when the temperature is lowered, the blades of grass become cool. As a result, the vapor molecules slow down and eventually come close to each other. They join together to form liquid water which gets deposited on the blades in the form of dew drops.
The only option that explains this process is option C.
The deltaHrxn = -243 kJ/mol the deltaHrxn of CH4(methane) = -802 kJ/mol
The fuel that yields more energy per mole is METHANE. The negative sign merely signifies the release of energy. Thus, 802 kJ/mol is greater than 243 kJ/mol.
The fuel that yields more energy per gram is HYDROGEN. Here is the computation:
deltaHrxn = (-243 kJ/mol)(1 mol/2.016 g H2) <span>= -120.535714286 kJ/g or -121 kJ/g
</span>deltaHrxn of CH4(methane) = (-802 kJ/mol)(1 mol/16.04 g)
<span>= -50 kJ/g
</span>
As discussed the negative sign serves as the symbol of released energy. Thus, 121 is greater than 50.
