How do u calculate the empirical formulae of an unknown compound a if it contains 46.6% of carbon, 13.6% of nitrogen, 8.47% of hydrogen and ? % of nb: ram of c= 12, h= 1, n= 14 and o= 16

C₄NH₉O₂

Explanation:

The question requires we determine the empirical for an unknown compound A.

Carbon-46.6%

Nitrogen - 13.6%

Hydrogen - 8.47%

Oxygen = 100% - (46.65 + 13.6% + 8.47%)

             = 31.28%

Step 1: Determine the moles of each element

Moles of Carbon = 46.6 ÷ 12

                            = 3.88 moles

Moles of Nitrogen = 13.6 ÷ 14

                              = 0.971 moles

Moles of Hydrogen = 8.47 ÷ 1

                                 = 8.47 moles

Moles of Oxygen = 31.28 ÷ 16

                             = 1.955 moles

Step 2: Determine the mole ratio of the elements

Mole ratio = C :  N : H : O

                = 3.88 moles : 0.971 moles : 8.47 moles : 1.955 moles

We divide by the smallest (0.971 moles )

               = 3.99 : 1 : 8.72 : 2.01

                = 4 : 1 : 9 : 2

     E.F      = C₄NH₉O₂

Therefore, the empirical formula of compound A is C₄NH₉O₂

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

the temperature of the gas, in k, not celsius.