2. If 6.0g of carbon is heated in air, the mass of the product obtained could be either 22.0g or 14.0g depending on the amount of air present. Show that this verifies the law of multiple proportions.

3. Alaxin, (C5H8)nO5, is a new malaria drug. Determine the molecular formula of alaxin if its relative molecular mass is 284.
(H = 1, C = 12, O = 16)
i dont seem to remeber

Respuesta :

2 . The ratio of 1:2 in the mass of second element, oxygen in CO and CO2 verifies the law of proportion.

3. [tex]C_{15}[/tex][tex]H_{24}[/tex][tex]O_{5}[/tex]  is the molecular formula of the new malaria drug given.

Explanation:

Balanced chemical reaction:

C + O ⇒   C0

C + O2  ⇒  CO2

law of multiple formulation states that when two elements combine to form a compound the ratio of the mass of elements is a whole number.

Carbon reacts with oxygen to produce:

         Mass of carbon      mass of oxygen          ratio of O in CO2 to O in CO

CO =    12                                16                                      3:4

CO2 = 12                                 32                                     3:8

 CO    6 gm                              8                                     3:4

  CO2   6                                 16                                    3:8

The ratio of the mass of  the second element i.e oxygen is CO:CO2 is 1:2, hence it shows law of multiple proportions.      

3. given,

 (C5H8)nO5 = emperical formula

relative molecular mass = 284

molecular formula= ?  

The value of n will be calculated as:

(12x5)+ (1x8)n + (16x5) = 284

(60 +8)n  + 80 = 284

68n + 80 = 284

68n = 284 - 80

68n = 204

  n = 3

Multiplying the emperical formula by n

(C5H8)3O5

[tex]C_{15}[/tex][tex]H_{24}[/tex][tex]O_{5}[/tex] is the molecular formula of the drug.