Answer: the molecular formula is C10H20O
Explanation:Please see attachment for explanation
Avagadro's law gives the relationship between volume of gas and number of moles of the gas. When the temperature and pressure are constant, volume is directly proportional to number of moles of gas.

V -volume and n - number of moles of gas.
parameters for the first instance are on the left side and parameters for the second instance are on the right side of the equation
initial number of moles n1 - N
n2 - 2N as the number of moles are doubled
V1 - initial volume - 2.10 L
V2 - final volume - V
substituting the values in the equation

V = 4.20 L
final volume is 4.20 L
Answer:
1-bromobutane, unlike others, will not be removed because it is an <em>alkane</em> and inert to concentrated sulfuric acid.
Explanation:
<em>Alkanes</em> are saturated organic compounds, primarily made up of hydrogen and carbon atoms. Saturation implies that they posses no double or triple bonds, therefore making them stable and unresponsive to addition reactions and also, concentrated sulfuric acid.
1-Butanol is a primary alcohol. Primary alcohols will react with acids to produce alkyl halides. 1-butene, as an alkene, will react with concentrated sulfuric acid to produce alkyl hyrgensulfate, while di-n-butyl will produce an ether when it reacts with concentrated sulfuric acid.
Therefore, these organic compounds will be washed and converted to other compounds by concentrated sulfuric acid except 1-bromobutane.