Ethanoic acid is the first member of caboxylic acid series

Ethanoic acid has the formula:

Ethanoic acid is weaker acid than benzoic acid.Why ?

Rydberg's constant is equal to 1.09678 . 10^7 m^(-1) .Calculate the wavelength of the first member of Lyman series.

The second member of Lyman series in hydrogen spectrum has wavelength of 5400overset@A .What is the wavelength of first member in the same series ?

In a reaction ,5.3g of sodium carbonate reacted with 6g of ethanoic acid. The product were 2.2 g of carbon dioxide,0.9g water and 8.2g sodium ethanoate. Show that these observation are in agrement with the law of conservation of mass. Sodium carbonate + ethanoic acid rarr sodium ethanoate + carbon dioxde + water.