A chemistry question??

Question

Answer these questions for N2O3

a. what is the number of moles of each kind of atom in 30,4g of the compound.

b.what is the number of mol of compound that contains 2,4g of Oxygen.

c.what is the mass of O2 combined with 2,8g of Nitrogen.

d.what is the mass of compound that contains 1,8.10"23" (ten to the 23th power) oxygen atoms.

e what is the mass of compound that contains 3,01.10"23" molecules

f. what are the percentages by mass of each element in the compound

these questions are related to the mole concept

and if anyone can answer these questions so please please please write the formula of that question too.

Answer 1

You need the molar mass (molecular weight, formula weight) equation.

MM = mass / mole  

and its conversion  (mass = moles x MM  and moles = mass / MM)

Calculate the molar mass

Element    -   Atomic Weight x Number of Atoms =  add this column

N    -    14.0  x 2  = 28.0

O   -     16.0 x 3  =  48.0

                           Total = 76.0 (your instructor may which more sig. figs)

a. moles = mass / mm = 30.4 / 78.0 = A

moles of nitrogen = A x 2

moles of oxygen = A x 3

b.  moles of oxygen = 2.4 / 16.0 = B

moles of compound = B /3

c.  2.8 grams of nitrogen = .2 moles of nitrogen

0.2 moles of nitrogen will react with 0.3 moles of oxygen atoms of 0.15 moles of O2

mass of oxygen = 0.15 moles x 32.0 g/mol = 4.8 g

d.  1.8 x 10^23 atoms of O /3 = 0.6 x 10^23 molecules = 6 x 10^22 molecules

moles of molecule = 6 x 10^22 / 6.022 x 10^23 (avogadro's number) = D

D x 78.0 = mass of the compound

e.  3.01 x 10^23 = 0.5 moles = 39.0 grams

f. % N = 28 / 78 x 100

%O = 48 / 78 x 100

Answer 2

A) Molar mass of N2O3 = 76.02 g

Use % mass to find out how much of the mass is O3 and how much is N2:

48 / 76.02 = 63.14%      (30.4)(63.14%) = 19.19 g O3

19.19 g x (1 mol / 16.00 g) = 1.20 mol Oxygen (atomic)

28.02 / 76.02 = 36.86%      (30.4)(36.86%) = 11.21 g N2

11.21 g x (1 mol / 14.01 g) = .800 mol Nitrogen (atomic)