Is vinegar and baking soda a acid-base reaction? ##CH_3COOH## and ##NaHCO_3##

Absolutely.

##H_3C-CO_2H(aq) + (Na^+)(HOCO_2^-) rarr [H_3C-CO_2^(-)Na^+] + CO_2(g)uarr +H_2O(l)##

When baking powder is added to a cake, the acid base reaction it undergoes with the acidic butter produces the carbon dioxide that makes the cake rise.