NO SCHOOL

Teacher training

4/8/13

STAPLE4/9/2013 Standards: 5 (Acids and Bases)Objectives: ●  Work CST problems with responders for CST Review (q's 59-64) ●  Students will be able to identify strong and weak acids. ●  Students will be able to Ka for any acid given its formula.DO NOW: 1. GET RESPONDERS AND SIGN-IN 2. Define: a. Strong Acid; b. Weak Acid; c. Strong Base; d. Weak BaseHOMEWORK: 1. Ch 19.2 p. 605 10 (a,b,c); 11 (a,b,c,d) (5 pts) Std 5 2. CST Problems 59-64 (5 pts) Std MISC

Follow these directions - Copy questions if no calculations and givereasons with page #'s or quote me if I gave explanation; for

calculation problems - given, find, and show calcs. ===========================================================STAMPING:   ●  Journal 4/5 (Fri last wk) 1. Ch 19.1 p. 601 PP's - 3. (a,b,c) and Ch 19.1 Assess. - 4-9 (5 pts) Std 5 2. CST Problems 53-58 (5 pts) Std MISC

Monday April 22 - Mr. Wigger'sCST

Page 601 - Ch 19.1 Assess Answers

DO NOW FIRST

HCl HNO3

STRONG ACIDS

H2SO4 HClO4

Metal with OH-

STRONG BASES

page 601answers

Reviewing Keq

1 In the expression below, what is letter ________ ?

A reactant

B product

C coefficient

D concentration

E exponent

F identifies substance

G all of these

a A b B c C d D

aA + bB -----> cC + dD

2 In the expression below, what is letter ________ ?

A reactant

B product

C coefficient

D concentration

E exponent

F identifies substance

G all of these

Keq =

[A]a[B]b

[C]c[D]d

a A bB

c C d D

CST Questions59-64

Demonstration of strong & weak acids using conductivity light:Page 602

Page 603What does a STRONG acid look like?

What does a WEAK acid look like?

Species - not like biology. They are any molecule or ion.

Examples:

Acid ====> Proton Donor

Base ====> Proton Acceptor

(H+ ion is a proton)

Bronsted-Lowry Acids & Bases

These guys are on the left side of the equation

without stamping, this presentation takes one whole period

conjugate acid - receives the donated proton

(H+ ion)

conjugate base - what is left of the acid after donating H+

Bronsted-Lowry Acids & Bases

These guys are on the right side of the equation

Hydrogen

neutral atom ion

(lost one electron)

H3PO4 + H2O <-----> H2PO41- + H3O1+

-

O-

+

H

O

--

+

H

-O-+H

+H

-O-

+

H+

H

-O-+H

+H

-O-+H

+H -O-+H

+H

-O-+ H

+ H

How water self-ionizes

+

H

+

H

Bronsted-Lowry Acids & Bases

self-ionization of water

reverse

Bronsted-Lowry Acids & Bases

ionization of ammonia in water

reverse

Bronsted-Lowry Acids & Bases

ionization of ammonia in water

reverse

Steps in the ionization of H3PO4

H3PO4 + H2O <---->

H2PO41- + H2O <---->

HPO42- + H2O <---->

Guided practice for Ka and Kb

CH3COOH + H2O <---->

H2S + H2O <---->

C2H5NH2 + H2O <---->

C6H5NH2 + H2O <---->

Guided practice for Ka and Kb

Ka for CH3COOH =

Ka for H2S =

Kb for C2H5NH2 =

Kb for C6H5NH2 =

STAPLE

4/10/2013 Standards: 5 (Acids and Bases)Objectives: ●  Work CST problems with responders for CST Review (q's 65-70) ●  Students will be able to create Ka   Kb   , and pH DO NOW: 1. no responders today 2. What powers of 10 = (a) .001, (b) .000003, (c) .00000000009HOMEWORK: 1. Ch 19.3 PP's p. 609   18 (a-c), Ch 19 Assess p. 631 87. (a,b); 88 (a,b)

(5 pts) Std 5 2. CST Problems 65-70 (5 pts) Std MISC

Follow these directions - Copy questions if no calculations and givereasons with page #'s or quote me if I gave explanation; for

calculation problems - given, find, and show calcs. ===========================================================STAMPING:   ●  Journal 4/9 1. Ch 19.2 p. 605 10 (a,b,c); 11 (a,b,c,d) (5 pts) Std 5 2. CST Problems 59-64 (5 pts) Std MISC

+

H

-

O-

+

H

+

H

O

--+

H

+

H

-O-+H

+H

-O-

+

H+

H

-O-+H

+H

-O-+H

+H

-O-+H

+H

-O-+ H

+ H

How water self-ionizes

+

H

O

--

KW = [H+] [OH-] [H2O(l)] <====> [H+] [OH- ]

+

H

+

H<====>

page 608compare to graphic

-

O-

1-

1+

pH = -log [H+]

pOH = -log [OH- ]

pH + pOH = 14

Kw = [H+] [OH1- ] = 10-14

compare #'s for values of pH & pOH in Kw

EXAMPLES BELOW

Homework Hellp

Problem type for homework on page 609 #18

Kw =

divide both sides by [H+]

Actual HW problem on page 631 #88b

Given

[H+] = 5.8 x 10-11

Find

pH = ?

NOTE: Question 87 a and b are both exactly like questions in #18 on p. 609

Problem

Solution

pH = -log [H+] = -log [ 5.8 x 10-11]

= ( -log [ 5.8 ] ) + ( -log [10-11] )

11+This log only needs to be estimated because it is insignificantly small. Here is what you do: if value = 2-3 = 0.3 if value = 4-6 = 0.7 if value = 7-9 = 0.9So -log [ 5.8 ] estimate = - 0.7

( -log [ 5.8 ] )

- 0.7

- 0.7 11+

pH = 10.3

For greater accuracy we need a log table like this one

http://mrwiggersci.com/chem/Tutorials/log-chart_1-10-estimating-logs-antilogs.htm

Or by going to http://mrwiggersci.com/chem/Tutorials.aspx Then select > Ch 19 : Acids & Bases > last entry at bottom of this section

Available on my website by clicking large blue dot below.

Ka

Kb

Equilibrium constant for an acid

Equilibrium constant for an base

Here is pH Meter simulator that lets you test pH different acids, bases, and salts.

http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/buffer12.swf

Here is an applet to let you see what happens in a "buffered" solution

http://group.chem.iastate.edu/Greenbowe/sections/projectfolder/flashfiles/acidbasepH/ph_meter.html

STAPLE4/11/2013 Standards: 5 (Acids and Bases)Objectives: ●  Polish skill gained so far in Ch 19.1-19.3DO NOW: 1. Due end of the period (7 pts) Std 5

Ch 19 Assess - p. 630 Copy questions, if multiple questions, do them all: 40-43, 46, 50, 52-55, 59, 60, 62-64. (23 questions)HOMEWORK: 1. CST Problems 71-76 (5 pts) Std MISC

Follow these directions - Copy questions if no calculations and givereasons with page #'s or quote me if I gave explanation; for

calculation problems - given, find, and show calcs. ===========================================================TURNED IN - BASKET: 1. Ch 19.3 PP's p. 609   18 (a-c), Ch 19 Assess p. 631 87. (a,b); 88 (a,b)

(5 pts) Std 5 2. CST Problems 65-70 (5 pts) Std MISC

4/12/2013 Standards: 5 (Acids and Bases)Objectives: ●  CST's 77-82 - Responders - will do Q's 77-80 only ●  Students will be able to calc. pH and pOH ●  Students will be able to use pH + pOH = 14 to convert pH to pOHDO NOW: 1. Review p. 609-611 18 (all) and 87 & 88 (all) and be ready to tell me

problems you don't fully understand.HOMEWORK: 1. Ch 19.3 Ch 19.2 p. 611-613 19 (a,b,c); 20 (a,b,c) (5 pts) Std 4 2. CST Problems 77-82 (5 pts) Std MISC

Follow these directions - Copy questions if no calculations and givereasons with page #'s or quote me if I gave explanation; for

calculation problems - given, find, and show calcs. ===========================================================STAMPED:   ●  Journal 4/11 (what you learned FROM your fellow

students, or what you taught to other students.) 1. CST Problems 71-76 (5 pts) Std MISC

Announcement - regarding CST's

Chemistry CST from State of Calif. happens 4/25

Chemistry CST from Wigger happens 4/23

Armenian Genocide Remembrance Assembly happens 4/24

4th day of testing

100 points (50 questions)

Estimates to use when calculating logs: if value = 2-3 <--> 0.3 if value = 4-6 <--> 0.7 if value = 7-9 <--> 0.9

If [H+] = 1.0 x 10-4

needs no estimates, simply pH of this conc = 4.0

If [H+] = 6.2 x 10-11 needs estimate for the 6.2 estimate would -0.7 + 11 = 10.3

Estimates to use when calculating logs: if value = 2-3 <--> 0.3 if value = 4-6 <--> 0.7 if value = 7-9 <--> 0.9

If [H+] = 1.0 x 10-4

needs no estimates, simply pH of this conc = 4.0

If [H+] = 6.2 x 10-11 needs estimate for the 6.2 estimate would -0.7 + 11 = 10.3