Answer:
Fractional distillation is used for the purification of water as well as separating acetone and water.
Fractional distillation is used in several industries like oil refineries and chemical plants mainly for purification and separation of many organic compounds.
The mass of magnesium should be less than 0.09g to enable a faster reaction rate. Magnesium reacts to form a white coating around it which stops the reaction. The lesser the gram the faster the reaction before the coating is formed. It is also advisable to use magnesium fillings to increase the rate of reaction.
(a) 485 x 200 mg = 97000 mg of ibuprofen in the bottle
97000 mg x (1g/1000mg) = 97g of ibuprofen in the bottle
97g (1 mol/ 206.5gC13H18O2) = 0.46973 moles of ibuprofen in the bottle
(b) 0.46973 mol C13H18O2 (6.022 x 10^23 molecules/1mol) = 2.8287 x 10^23 molecules of ibuprofen in the bottle
Answer: 46. E 47. D 48. C 49. A
50. A 51. D 52. B 53. B 54. C
Explanation: solution attached.
First things first carbon is quite common element here in Earth. But it is not all, right? Otherwise we would be built from other, more common elements. The thing is in carbon reactiveness. Also energy needed to create carbon chemical compounds isnt that big when compared to etc nitrogen. It can bind up to 4 different elements (atoms). Thanks to this can givesingle, both and triple bindings! Carbon can give away electrons or take them making his degree of oxidation consequently from -IV to +IV. All this vareity leads to vareity of bigger elements that will be created from carbon later- carbohydrates, proteins etc. As life needs vareity to adapt to different situations and climax only carbon therefore can provide this.
