What si the percent composition of each element in the coumpound hydrogen cyanide?

Question

What is the moleculare formula for the coumpouns whoe empirical formula is CH(small2)O an dhas a molar mass of 90.0 g/mol

how many moles are in .247 grams of irom II oxide

Answer 1

Percent comp is determined by first getting the atomic mass of each of the atoms in the formula:

H ~1 amu, C ~12amu, N ~14amu

Add these up to get 27amu. Now to get percent, divide each of the individual amu's by the total (remember that % means part to the whole x 100)

Ex: 1/27 x 100 = 3.7%.....you do the C and N

Molecular formula is similar: add up the atomic masses of each of the atoms: 1C + 2H + 1O

Now divide this mass by the molar mass. This will tell you how many times you need to multiply the subscripts of each atom to get the molecular formula.


Moles can be calculated by using moles/gram conversion. Get the mass of iron II oxide and convert to moles.

Answer 2

Not enough information. Instead, you might ask, "Calculate the percent composition of EACH SPECIES in these compounds..." ... in which case you would calculate the amount in grams of one species in the molecule and divide by the total amount in grams of one mole of the species. Example: What is the % composition of Carbon in C2H6. %Composition = (mass of 2*C)/(mass of 2 x C + 6 x H) x 100% = 2*12 / ( 2 x12 + 6 x 1 ) = 24/ 30 * 100% = 77.4 % Carbon.

Answer 3

Hydrogen cyanide goes by the formula-HCN. Percentage composition of each of the element is as follows-

Hydrogen-3%, Carbon-4% and Nitrogen-57%

Sri