A gaseous compound containing carbon and hydrogen was analyzed and found to consist of 83.65% carbon by mass. What is the empirical formula of the compound

Explanation:

The empirical formula of a compound represents the ratio of elements present in it but not the actual number of atoms.

Let the total mass of compound is 100 gram.

Then  mass of carbon would be is 83.65 gram .

Moles of carbon = 83.65/12 = approx 7 mole  (approx)

Mass of hydrogen present in the compound would be 100 - 83.65

                                                                                        = 16.35  gram

Moles of hydrogen = 16.35/1 = 16 mole (approx)

Therefore, the empirical formula of the compound would be

i just learnt this recently but i need to look through my notes again

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.