Answer:
The first is the empirical formula which shows you the number of different atoms in the compound. After you convert the grams of each element into moles, you calculate the ratio of the moles, which gives you the ratio of the elements in the compound. More number-crunching gives you the molecular formula.
120.38 g/mol is the answer
Since you didn't give the actual volume (or any of the experimental values) I can only tell you how to do it. Do the calculation using the real (determined) volume of the flask. Then, re-do the calculation with v = 125ml. Take the two values and calculate % error; m = measured vol; g = guessed vol.
<span>[mW (m) - mW (g)]/mW (m) x 100% </span>
<span>(they want % error so, if it is negative, just get rid of the sign) </span>
First, find the total mass.
34.5 g + 18.2 g + 2.6 g = 55.3 g
Divide the mass of each element by total mass.
34.5 g / 55.3 g = .62 x 100 = 62% element a
18.2 g / 55.3 = .33 x 100 = 33% element b
2.6 g / 55.3 = .047 x 100 = 4.7% element c
Hope I helped!
As you move around there is a change in: electronegativies, ionisation energies, atomic radius etc. different amounts of these properties are going to effect how the element acts
