The composition by mass of a compound is: C=36.4%, H=6% and F=57.6%. Calculate the empirical formula. If the RFM is 66, what is the molecular formula?
Calculate the moles of each of the 3 elements (to get C=3.03, H=6, F=3.03). Divide these by the smallest mol calculated to get the ratio of the elements. This will get C:H:F as 1:1.978:1 = 1:2:1 and so the empirical formula is CH2F. The RFM is 66, 66/33 is 2 and so the molecular formula is C2H4F2
ST
Related Chemistry GCSE answers
All answers ▸What is the volume of a gas in a closed system working under ideal conditions at r.t.p of 1.5 moles of gas?
Describe how ethanol can be produced from ethene
The student did another experiment using 20 cm3 of sodium hydroxide solution with a concentration of 0.18 mol/dm3 . Relative formula mass (Mr) of NaOH = 40 Calculate the mass of sodium hydroxide in 20 cm3 of this solution.
Name or formulate these compounds: i)CH3CH2CH(CH3)COOH ii)CH3CH2COCH3 iii) 3-hydroxy-2-pentanone iv) 1-propanamine