CHEM1011 Lecture Notes - Lecture 4: Ideal Gas Law, Intermolecular Force, Lone Pair

52 views2 pages

carmineporpoise43

31 May 2018

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

CHEM1011 – Chemistry 1A – Part 2

LEC 4: Acid and Base

Theory

• Acid [H+]:

o Proton donor

o Must contain a H

o Can be positively, negatively or neutrally charged

▪ E.g. HCl, H3O+, NH4+, H2SO4, H2CO3 (carbonic acid)

• Base [OH-]:

o Proton acceptor

o Must contain a lone pair of electrons to bind to H+ ion

o Can be negatively charged or neutral

▪ E.g. Cl-, OH-, NH3

• Amphiprotic: can act as an acid or base

• Conjugate pairs:

• Strong vs weak:

o Strong acid: acid that dissociates completely into its H+ ions

▪ HCl, HBr, HI (+ O3, and O4), HNO3, H2SO4

o Weak acid: acid that only dissociates partly into its H+ ions

o Strong base: base that dissociates completely into OH-

▪ LiOH, NaOH, KOH, Ca(OH)2

o Weak base: base that only partly dissociates into OH-

• Concentration: conc. depends on how the substance has been diluted

• pH: determined by both strength and concentration

• Common acids: Sulfuric acid H2SO4, Nitric acid HNO3, Acetic acid CH3CO2H

• Common bases: Calcium carbonate CaCO3, Sodium hydroxide NaOH, Ammonia NH3

• Acid reactions:

o Neutralisation: acid + base → salt + water

o Carbonates: acid + carbonate → salt + CO2(g) + water

o Metals: acid + metal → salt + H2(g)

Calculations

• Titration:

1. Start with volume of known concentration

2. n = C x V to find moles of known solution

3. Using mole ration (from equation) find moles of unknown solution

4. C = n/V to find conc. of unknown solution

LEC 5: Gases

Theory

find more resources at oneclass.com

Unlock document

This preview shows half of the first page of the document.
Unlock all 2 pages and 3 million more documents.

Already have an account? Log in

Document Summary

Theory: acid [h+], proton donor, must contain a h, can be positively, negatively or neutrally charged, e. g. +, h2so4, h2co3 (carbonic acid: base [oh-], proton acceptor, must contain a lone pair of electrons to bind to h+ ion, can be negatively charged or neutral, e. g. Calculations: titration, start with volume of known concentration, n = c x v to find moles of known solution, using mole ration (from equation) find moles of unknown solution, c = n/v to find conc. of unknown solution. Theory: boyle"s la(cid:449): at fixed temperature and moles, as pressure increases, volume. 1 pa = 1 n m-2, 1 bar = 1 x 105 pa. P1v1 (initial) = p2v2 (final: charles" la(cid:449): at fixed pressure and moles, as temperature increase, volume, a(cid:448)ogadro"s la(cid:449): at fixed temperature and pressure, as volume increases, moles decreases. Pressure = pascal (pa: gas pressure and measurement: pressure = (cid:2916)orc(cid:2915) (cid:4666)n(cid:4667) ar(cid:2915)a (cid:4666)m2(cid:4667)

Related Questions

1.Phenolphthalein is, HPhen, is a common acid-base indicator. In solutions it dissociates according to the equation:

Le Châtelier’s Principle 8
HPhen(aq) ---> H+(aq) + Ph-(aq)
clear (HPhen = weak acid) pink (Ph- = conjugate base)
If phenolphthalein is added to distilled water, the solution is clear. If a drop or two of 6 M NaOH is added to the clear solution, it turns bright pink. If to that solution one adds a few drops of 6 M HCl, the color reverts to clear.

a. Give the net ionic equation for the reaction that happens when NaOH is added to phenolphthalein. Why does adding 6 M NaOH to the clear solution of phenolphthalein tend to cause the color to change to pink? (Note that in solution NaOH exists as Na⁺ and OH^- ions.)
b. Give the net ionic equation for the reaction that happens when HCL is added to phenolphthalein. Why does adding 6 M HCl to the red solution tend to make it turn back to clear? (Note that in solution HCl exists as H⁺ and Cl^- ions.)

2. Iron(III) hydroxide is only very slightly soluble in water. The reaction by which it goes into solution is:
Fe(OH₎₃(s) Fe ³⁺(aq) + 3 OH^-(aq)

a. Formulate the expression for the equilibrium constant, Ksp, for the above reaction.
b. Explain why Fe(OH)3 might have very appreciable solubility in 1 M HCl. (Consider the effect of Reaction 2 on the Fe(OH)3 solution reaction.)

burgundycicada286

Part A A fuel cell differs from a battery because the current is being generated from a reduction-oxidation (redox) reaction in which the reactant is consumed. A classic example of a fuel cell is the phosphoric acid fuel cell (PAFC), which have been used in stationary power generators, buses, and even submarines. Fuel cells require an electrolyte (similar to batteries) to carry electrically charged species between the electrodes, and a PAFC utilizes phosphoric acid (H3PO4) as its electrolyte. Phosphoric acid has three acidic protons that can dissociate in water, as highlighted in red here: H3PO4. However, it is considered a weak acid because some of the acid will remain in molecular form when dissolved in water. Write the complete ionic equation that depicts the dissociation of the first proton for the weak acid phosphoric acid (H3PO4). Make certain you include all charges for any ions produced. Express you answer as a chemical equation including phases. Titrations as analytical neutralization reactions Neutralization reactions can occur between any combination of weak/strong acids and bases. When we want to determine the concentration of a base in solution, we can apply the concept of neutralization by reacting the base with a known amount of an acid in the presence of an indicator (a compound that changes color depending on the pH). This method of determining the concentration of a base is called acid-base titration, and it can also be used to determine the concentration of an acid by titrating it with a known amount of base. A common acid to use for titrations is potassium hydrogen phthalate (written as KHP or KHPh; do not confuse the P for phosphorus). The reason KHP is common is because it is solid at room temperature, and we can accurately mass the amount that is added to solution. As a soluble salt, KHP completely dissociates to form a potassium ion (K+) and an acidic hydrogen phthalate ion (HPâ), which is a weak acid that has only one acidic hydrogen. This ionization is depicted below. KHP(s) â K+(aq)+HPâ(aq) Although ionization (the formation of ions) occurs as a result of acid dissociation for most weak acids, KHP ionizes before acid dissociation occurs. In other words, HPâ is a weak acid ion. Part C If you wanted to determine how much KOH (potassium hydroxide; a strong base) was dissolved in water, you could titrate it with a known amount of KHP (potassium hydrogen phthalate; a weak acid) until a color change indicates that the base is completely neutralized. The molecular equation below depicts this neutralization reaction. KHP(aq)+KOH(aq)âK2P(aq)+H2O(l) Write the net ionic equation that depicts the neutralization of the base by potassium hydrogen phthalate. Instead of using the entire chemical formula of phthalate, use HPâ to represent the acidic hydrogen phthalate ion and P2â to represent the phthalate ion. Express your answer as a net ionic equation including phases.

CHEM1011 Lecture Notes - Lecture 4: Ideal Gas Law, Intermolecular Force, Lone Pair

Document Summary

Get access

Related textbook solutions

Chemistry: Structure and Properties

Basic Chemistry

Principles of Chemistry Molecular Approach

Principles of Chemistry Molecular Approach

Chemistry: Structure and Properties

Chemistry: A Molecular Approach

Chemistry: A Molecular Approach

Principles of Chemistry: A Molecular Approach

Chemistry: The Central Science

Related Documents

CHEM1011 Study Guide - Equivalence Point, Calorimeter, Vapor Pressure

CHEM 130 Lecture Notes - Lecture 22: Lithium Hydroxide, Sodium Hydroxide, Ammonia

CHE-1102 Lecture Notes - Lecture 6: Conjugate Acid, Strong Electrolyte, Lithium Hydroxide

Related Questions