Is Llibr Acidic Basic or Neutral | Answer Key

University:
Campbell University
Course:
CHEM 111 | General Chemistry I
Academic year:

2020
Views:

274

Pages:

1
Author:

Focalimoicy3go

KEY Hydrolysis of Salts 1.) Write the hydrolysis of a salt reaction in water and discern if the solution is acidic, basic, or neutral. LiBr  Li+ + Br- a.) LiBr neither undergoes hydrolysis as both ions are spectators as they come from strong acids or bases. b.) K2CO3 K2CO3 ↔ K+ + CO3-2 CO3-2 + H2O ↔ HCO3 + OH- Basic c.) Na2HC6H5O7 Na2HC6H5O7 ↔ 2Na+ + HC6H5O7-2 this is amphiprotic!!!!! acting as an acid HC6H5O7-2 + H2O ⇌ C6H5O7-3 + H3O+ acting as a base HC6H5O7-2 + H2O ⇌ H2C6H5O7- + OH- ‫ܭ‬௔ = 4.1 × 10ି଻ Which one??? 7.1 × 10ିସ × ‫ܭ‬௕ = 1.00 × 10ିଵସ ‫ܭ‬௔ × ‫ܭ‬௕ = ‫ܭ‬௪ ‫ܭ‬௕ = 1.4 × 10ିଵଵ ‫ܭ‬௔ > ‫ܭ‬௕ = ‫ܭ‬௔ it acts as an acid!!! d.) NH4F NH4F ↔ NH4+ + F‫ܭ‬௔ = 5.6 × 10ିଵ଴ F- + H2O ↔ HF + OH- NH4+ + H2O ↔ NH3 + H3O+ and 3.5 × 10ିସ × ‫ܭ‬௕ = 1.00 × 10ିଵସ ‫ܭ‬௔ × ‫ܭ‬௕ = ‫ܭ‬௪ ‫ܭ‬௔ ሺܰ‫ܪ‬ସ ା ሻ > ‫ܭ‬௕ ሺ‫ ି ܨ‬ሻ = ݉‫ݐ ݁݀ܽ݉ ି ܪܱ ݁ݎ݋‬ℎܽ݊ ‫ܪ‬ଷ ܱ ା 2.) Why are the following two solutions both only slightly basic: ‫ܭ‬௕ = 2.9 × 10ିଵଵ it acts as an acid!!! 0.1 ‫ܱܰܽܰ ܯ‬ଶ and saturated ‫݁ܨ‬ሺܱ‫ܪ‬ሻଷ ? NaNO2 ↔ Na+ + NO2- NO2- + H2O ↔ HCO2 + OH- Fe(OH)3 (s) ↔ Fe+3 + 3OH- strong base so complete dissociation BUT Fe(OH)3 is low solubility!!! 3.) Arrange the following from highest pH to lowest pH: NH4Cl ↔ NH4+ + ClHCl weak base = low {OH-] NH4Cl, HCl, NaCH3COO, NH4CH3COO, NaOH. NH4+ + H2O ↔ NH3 + H2O ‫ܭ‬௔ = 5.6 × 10ିଵ଴ strong acid NaCH3COO ↔ Na+ + CH3COO- CH3COO- + H2O ↔ CH3COOH + H3O+ NH4CH3COO ↔ NH4+ + CH3COO- CH3COO- + H2O ↔ CH3COOH + H3O+ and ‫ܭ‬௔ × ‫ܭ‬௕ = ‫ܭ‬௪ NH4+ + H2O ↔ NH3 + H3O+ 1.8 × 10ିହ × ‫ܭ‬௕ = 1.00 × 10ିଵସ strong base weak base ‫ܭ‬௔ = 5.6 × 10ିଵ଴ ‫ܭ‬௕ = 5.6 × 10ିଵ଴ ‫ܭ‬௔ ሺܰ‫ܪ‬ସ ା ሻ = ‫ܭ‬௕ ሺ‫ܪܥ‬ଷ ‫ ିܱܱܥ‬ሻ = ‫ܪ ݏܽ ݁݀ܽ݉ ି ܪܱ ݁݉ܽݏ‬ଷ ܱା NaOH weak acid it acts neutral!! Final answer = NaOH, NaCH3COO, NH4CH3COO, NH4Cl, HCl