Question

SCUSSION: a Cach of the following formularenrogantongileidid which might b ed in US ON The replaceable (acidic) hydrogens are denoted by bold-face ve for each formula, give the number of moles which is one equivalent. a. Benzoic acid HC7H5O2 H3C6H5O7(H2O)3 9. Potassium hydrogentartrate h. Sodium hydrogenoxalate-1-water b. Citric acid-1-water KHCH4O6 NaHC204(H20) NaHSO4 c. Potassium hydrogenoxalate KHC204 1. Sodium hydrogensulfate d. Oxalic acid-2-water e. Potassium hydrogenphthalate H2C204(H20)2 2 KHC8H404 . Sodium hydrogentartrate-1-water k. Sodium dihydrogenphosphate 5-water NaHCAHAO(H20) ^ NaH2PO4(H20)5 2 KHSO4 1 . Tartaric acid f. Potassium hydrogensulfate H₂C AHAO2 ?

Answer 1

a. 1- Because only one H atom is available for donation for generation of Lewis base. Thus one mole has one equivalent.

b. 3- Citric acid is a tribasic acid with three donatable H atoms. Thus, one mole has 3 equivalents.

c. 1- Because ionisation of one molecule gives only one H atom. Thus, one mole has one equivalent.

d. 2- Oxalic acid is dibasic acid, with 2 H atoms available on dissociation. Thus, one mole has 2 equivalents.

All the given formulae of compounds have their acidic H atoms in bold face. Number of acidic Hydrogen denotes the basicity of the acid, which in turn denotes the number of equivalents per mole of the acid.