Consider a compound that is 31.17% c, 6.54% h, and 62.29% o by mass. assume that we have a 100 g sample of this compound. also consider that the molecular formula mass of this compound is 231.2 amu. what are the subscripts in the actual molecular formula for this compound?

 The molecular formula will be

Explanation:

If percentage are given and we are given total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of C= 31.17 g

Mass of H = 6.54 g

Mass of O = 62.29 g

Step 1 : convert given masses into moles.

Moles of C =

Moles of H=

Moles of O =

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For C=

For H =

For O =

The ratio of C: H: O= 1: 2.5: 1.5

Converting them into whole number ratios by multiplying by 2.

Hence the empirical formula is

The empirical weight of = 2(12)+5(1)+3(16)= 77 amu

The molecular weight = 231.2 amu

Now we have to calculate the molecular formula.

The molecular formula will be=

The molecular formula will be

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.