Which statement about the melting and boiling points of water and fluorine molecules is true?
a)the melting and boiling points of both molecules are the same.

b)the melting point of fluorine is higher than that of water.

c)the boiling point of water is higher than that of fluorine.

d)the melting and boiling points depend on the repulsive forces between the molecules of the compounds.

The correct answer is

C - The boiling point of water is higher than that of fluorine.

:)

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"