Which weak acid would be best to use when preparing a buffer solution with a ph of 9.80?

Certain solution possesses the ability to resist an appreciable change in hydrogen ion concentration  (i.e, pH) when small amount of acids or bases are added to these solutions. The resistance of solution is called 'Buffer capacity' and the solutions are called 'Buffer solutions'.Buffer solution usually consist of weak acid or base along with its salt. Equivalent mixture of Glycine and its salt with sodium hydroxide  is used for preparing buffer solution with pH equal to 9.80.

frequency, z, and the collision density, z, in carbon dioxide (co2), r 180 pm at 30 °c and 120 kpa

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.