I'd say the answer is D because they need to intake and keep as much water as possible.
Considering ideal gas behavior, the volume of 1 mol of gas at STP is 22.4 L; then the volume occupied by 1.9 moles is 1.9mol*22.4L/mol
The answer is 43 L if I am correct.
Answer : To determine enthalpy of solution for a solid with δH values.
One can use the equation as H (reaction) = H (products) - H (reactants)
If δH values are known one can simply substitute them in the above equation and get the enthalpy of the required solution.
Answer : 7.87 X

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Explanation : To find the fraction of schottky defects in the given lattice of CsCl,
we use the formula,

on solving with the given values ,

and T as 645 + 273 K and rest are the constants.

we get the answer as 7.87 X

.
Answer:
A. Energy
B. Chemical potential
C. Endothermic reaction
D.The law of conservation of mass
E. Transfers of energy