The empirical formula should be first determined. Empirical formula is the simplest ratio of whole numbers of components in a compound.
for 100 g of the compound
C H Cl
mass 46.47 g 7.80 g 45.72 g
number of moles 46.47 g/12 g/mol 7.80 g/1 g/mol 45.72 g/35.5 g/mol
= 3.87 mol = 7.80 mol = 1.29 mol
divide all by the least number of moles
3.87/1.29 = 3 7.80/1.29 = 6.04 1.29/1.29 = 1
when they are all rounded off to the nearest whole number
number of atoms are as follows
C - 3
H - 6
Cl - 1
the empirical formula is C₃H₆Cl
molecular formula is the actual number of components in the compound
molar mass = 155.06 g/mol
we have to find the mass of the empirical unit
mass of C₃H₆Cl - (12 g/mol x 3) + (1 g/mol x 6) + (35.5 g/mol x 1) = 77.5
we have to then find how many empirical units are in the molecular formula
number of units = molecular mass / empirical unit mass
= 155.06 g/mol / 77.5 = 2.00
there are 2 empirical units
molecular formula = 2 (C₃H₆Cl)
molecular formula - C₆H₁₂Cl₂
Answer:
FAS concentration = 1.61*10^-4M
Explanation:
Beer Lambert's law relates the absorbance (A) of a substance to its concentration (c) as:
where ε = molar absorption coefficient
l = path length
A plot of 'A' vs 'c' gives a straight line with slope = εl
In addition absorbance (A) is related to % Transmittance (%T) as:
A = 2-log%T----(2)
For the FAS solution, the corresponding calibration fit is given as:
y = 3678(x) + 0.056
This implies that the slope = εl = 3678
It is given that %T = 25.6%
Based on equation(1):
Answer:
1.2*10^24 molecules of CF4
Explanation:
the molar mass of cf4 is 88.0043 g/mol
176/88.0043 = 2 moles of CF4
Then multiply by avogadro's number (6.022*10^23) to get the number of molecules
2*6.022*10^23 = 1.2*10^24 molecules of CF4
The reaction equation is:
Li + Br → LiBr
39 grams of Li = 39 / 7 = 5.57 moles of lithium
41.5 grams of Br = 41.5 / 80 = 0.52 mole of bromine