Respuesta :
Answer:C6H7N = C12H14N2
C2HCl = C6H3Cl3
C5H10NS2 = C10H20N2S4
Explanation:
There are certain steps you need to follow to find the molecular formula:
1. Determine the number of moles = subscript
So for the first one
C has 6 moles
H has 7 moles
N has 1 mole
2. Multiply moles by atomic mass = atomic mass found on periodic table
So...
6 × 12 = 72
7 × 1 = 7
1 × 14 = 14
Then we going to add all of them together to get the empirical weight:
72 + 7 + 14 = 93
3. Divide molar mass by the empirical weight
So
186.24 ÷ 93 = 2
4. Multiply each mole by molecular weight
So...
2(C6H7N) = C12H14N2 = Molecular formula
Answer:
(a) [tex]C_{12}H_{14}N_2[/tex]
(b) [tex]C_{6}H_{3}Cl_3[/tex]
(c) [tex]C_{10}H_{20}N_2S_4[/tex]
Explanation:
Molecular formulas is the actual number of atoms of each element in the compound while empirical formulas is the simplest or reduced ratio of the elements in the compound.
Thus,
Molecular mass = n × Empirical mass
Where, n is any positive number from 1, 2, 3...
(a) [tex]C_6H_7N[/tex]
Mass from the Empirical formula = 6×12 + 7×1 + 1×14 = 93 g/mol
Molar mass = 186.24 g/mol
So,
Molecular mass = n × Empirical mass
186.24 = n × 93
⇒ n ≅ 2
Molecular formula = [tex]C_{12}H_{14}N_2[/tex]
(b) [tex]C_2HCl[/tex]
Mass from the Empirical formula = 2×12 + 1×1 + 1×35.5 = 60.5 g/mol
Molar mass = 181.44 g/mol
So,
Molecular mass = n × Empirical mass
181.44 = n × 60.5
⇒ n ≅ 3
Molecular formula = [tex]C_{6}H_{3}Cl_3[/tex]
(c) [tex]C_5H_{10}NS_2[/tex]
Mass from the Empirical formula = 5×12 + 10×1 + 1×14 + 2×32 = 148 g/mol
Molar mass = 296.54 g/mol
So,
Molecular mass = n × Empirical mass
296.54 = n × 148
⇒ n ≅ 2
Molecular formula = [tex]C_{10}H_{20}N_2S_4[/tex]