Question

A former high school teacher was discovered making meth, and the dea recently analyzed some confiscated material from a drug bust he was associated with. they found a compound with the empirical formula c17h14o7 that has a molar mass of 990.87 g/mol. what is the value of n (the multiplier) necessary to find the molecular formula?

Answer 1

n = 3. (I know I'm answering this a week later, still hope this helps you understand the concept.) C17H14O7 has a molar mass of 330.29 g/mol. An empirical formula is essentially just a chemical formula simplified down to it's most common denominator of the subscripts. Dividing 990.87 g/mol by 330.29 g/mol gives us 3, the value of n. To go further, the chemical he was using was C51H42O21, or... (2R,2'R,2''R,3R,3'R,3''R,4R,4'R,4''S)-2,2',2''-Tris(3,4-dihydroxyphenyl)-4''-(2,4,6-trihydroxyphenyl)-3,3',3'',4,4',4''-hexahydro-2H,2'H,2''H-4,8':4',8''-terchromene-3,3',3'',5,5',5'',7,7',7''-nonol, whatever the hell that is.

Answer 2

Answer:

3 is the value of n necessary to find the molecular formula.

Explanation:

The equation used to calculate the valency is :

$n=\frac{\text{molecular mass}}{\text{empirical mass}}$

We are given:

Mass of molecular formula = 990.87 g/mol

Mass of empirical formula of $C_{17}H_{14}O_7$:

$12 g/mol+17+1 g/mol\times 14+16 g/mol\times 7=330 g/mol$

Putting values in above equation, we get:

$n=\frac{990.87 g/mol}{330 g/mol}=3.00$

3 is the value of n necessary to find the molecular formula.

The molecular formula is : $C_{51}H_{42}O_{21}$