For the following unbalanced equation: Ca(s) + H2O(1)→ H2(g) + Ca(OH)2 a. Balance the equation.
b. How many g of Ca are needed to react with 10.3 moles H2O?
C. How many g of H2 can be produced from 324 g Ca?
d. If 33 L H2 are produced at STP, what mass of Ca(OH)2 must also be
produced?

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Explanation:

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.