<u>Answer:</u> The number of moles of calcium metal required is 2.0 moles.
<u>Explanation:</u>
We are given:
Moles of water reacted = 4.0 moles
The given chemical reaction follows:
By Stoichiometry of the reaction:
2 moles of water is reacted with 1 mole of calcium metal
So, 4.0 moles of water will react with = 
of calcium metal
Hence, the number of moles of calcium metal required is 2.0 moles.
Answer:
Keq =1.50108
Explanation:
The given reactionis
C₂H₂(g) +2H₂(g) -------------> C₂H₂(g)
ΔG0 f=ΔG0f n (products) - ΔG0f n (reactants )
= -32.89 kJ/mol - (209.2 kJ/mol+2*0.0 kJ/mol)
= - 242.09kJ/mol
ΔG= -RTlnKeq
ln Keq = -ΔG/RT
=-(- 242.09kJ/mol ) / 2 k cal /mol*298 K
=0.406
Keq =e0.406
Keq =1.50108
The answer would be evaporation takes place at the surface of an ocean, lake, stream, or other body of water
