Using the law of constant proportions which says that within the same compound, elements exist in fixed ratios.
Therefore; we can use the ratio of total mass to the mass of carbon, to determine the amount of carbon in another sample.
Mass C / Mass CH4 = Mass C / Mass CH4
43.2 g / 57.6 g = Mass C / 37.8 g
Mass C = 37.8 g × 43.2 g / 57.6 g
= 28.35 g
Hence; the percentage of carbon will be;
=(28.35/ 37.8 )× 100%
= 75 %
Thus; 75% of 37.8 g of methane is carbon
Answer:
hope this helped :( got this from my friend a long time ago but still not sure if it's really correct this
The relative volumes of chloroform and water that should be used is 9:10
Concentration of solution in chloroform =
( moles of chloroform )
Concentration of solution in water =
( moles of water )
Dissociation constant at
; 
Concentration of solution in chloroform / Concentration of solution in water
Meaning;

Since
mole is present in chloroform and
mole is present in water, Total mole of Caffeine present is 
Now, we substitute our given values into the equation

Therefore, the relative volumes of chloroform and water that should be used is 9:10
Learn more; brainly.com/question/11060225
Correct answer to this question is c. water evaporating
It is false, hope this helps!