ION CONCENTRATIONS pH and pOH Calculations.  The pH scale is used to identify a substance as an acid or a base due to the pH value.  This scale is a.

Slides:

Advertisements

Similar presentations

PH worksheet (#1).

Advertisements

Ways to measure Acidity/Basicity What is pH? What is pOH?

Acids and Bases. Ionization of Water H 2 O + H 2 O H 3 O + + OH - K w = [H 3 O + ][OH - ] = 1.0 

Continuing into the world of acids and bases….  pH of a solution is the negative logarithm of the hydrogen ion concentration  pH = -log [H + ]  This.

Unit: Acids, Bases, and Solutions

The pH concept  [H + ] is cumbersome so the pH scale was created.  pH is the negative logarithm of the hydrogen-ion concentration.  pH = -log[H + ]

Wake-up Write down each equation below. Identify the base (B), acid (A), conjugate acid (CA), and conjugate base (CB). 1.NH 3 + HCN  NH 4 + CN 1.HSO 4.

Calculating pH and pOH. pH pH = - log [H + ] [H + ] = the hydrogen ion concentration pH: “potential of hydrogen” - A way of expressing the hydrogen ion.

Strength of Acids and Bases. What makes a strong acid or base?  The strength of an acid or base is based on how many acid or base particles break down.

Chemistry Notes: pH Calculations Chemistry

PH P ractice Practice Problem # 1 © Mr. D. Scott; CHS If the hydrogen ion concentration of a solution is 2.5 x M, what is the pH of the solution?

pH scale Measures the amount of H + in a solution. Scale used to measure whether a substance is an acid or a base. Lower numbers are acids. Higher numbers.

Here’s another example calculation question involving these quantities [H 3 O + ], [OH – ], pH, and pOH Calculations Example 2.

The Chemistry of Acids and Bases. Acids and Bases: Calculate pH/pOH At the conclusion of our time together, you should be able to: 1. Change any pH reading.

© Carey Munoz First, fold your paper in half like this. Not this. pH, pOH, [H + ], [OH - ]

pH scale Logarithmic scale expressing the H + concentration, [H + ]. If the pH changes by a factor of 1, the [H + ] changes by a factor of 10. pH =

PH Chapter Vocabulary Word hydronium ion: H 3 O + hydroxide ion: OH -

Section 16.2 Determining the Acidity of a Solution 1.To understand pH and pOH 2.To learn to find pH and pOH for various solutions 3.To use a calculator.

Molarity, Dilution, and pH

Chemistry Notes pH and [H + ] Working with the Arrhenius acid definition, we say that acids produce hydrogen ions: HX  H + + X - And bases produce hydroxide.

Ch. 18: Acids & Bases Sec. 18.3: What is pH?. Objectives n Explain the meaning of pH and pOH. n Relate pH and pOH to the ion product constant for water.

What is pH?. Ion Product Constant for Water  H 2 O(l)  H + (aq) + OH - (aq)  Keq = Kw = [H + ] x [OH - ]  The ion product constant for water (Kw)

14.3 pH Scale 14.4 pH of Strong Acids

Chemistry Chapter 19 Practice with acids and bases.

* Name the following acids: * HI * HNO 3 * HCl * Write the formula for the following acids: * Hydrofluoric Acid * Nitrous Acid * Hydrobromic acid.

Pg  Amphoteric substance: can act as an acid or as a base ◦ Water is the most common amphoteric substance  Self-ionization of water: H 2.

Let’s take a look at water  2H 2 O  H 3 O + + OH -  [H 3 O + ][OH - ]= 1x M 2  [H 3 O + ]= 1x10 -7 M  [OH - ]= 1x10 -7 M  K w = 1x M.

Yesterday’s Homework Page 611 # 19 Page 612 # 20.

Ch. 15 & 16 - Acids & Bases II. pH (p ) C. Johannesson.

NOTES: 19.2 – Hydrogen Ions & Acidity (pH and pOH)

C. Johannesson Ch. 15 & 16 - Acids & Bases II. pH (p )

Acids & Bases pH. Ionization of Water H 2 O + H 2 O H 3 O + + OH - K w = [H 3 O + ][OH - ] = 1.0  Kw=ionization constant for H2O.

PH And pOH. Water Water autoionizes H 2 O + H 2 O H 3 O+ + OH- Hydrogen ion concentration determines the acidity of the solution Kc = [H3O+][OH-] ionization.

pH scale Logarithmic scale –expressing H +1 concentration, [H +1 ] If pH changes by factor of 1, [H +1 ] changes by a factor of 10 pH = -log[H +1 ]pH.

pH scale Logarithmic scale –expressing H +1 concentration, [H +1 ] If pH changes by factor of 1, [H +1 ] changes by factor of 10 pH = -log[H +1 ]pH.

[H 3 O + ] Aqueous Solutions Brackets means concentration (Molarity) 1x10 -7 M neutral 1x10 -5 M 1x10 -9 M acidic = > [OH - ] acid base M

PH. Ionization of Water  When compounds dissociate/ionize in an aqueous solution, they produce ions - hydronium (H 3 O + ) and hydroxide (OH - )  These.

Acids and Bases Bundle 4: Water.

PH Calculations.

PH calculations More in depth than you need for 1st year, but requests were made, so here goes.

The pH Scale Hydronium & Hydroxide Ions (H3O+) (OH–) pH Scale

PH scale “power of hydrogen”.

Molarity, Dilution, and pH

Ch. 19 Acids & Bases II. pH.

DO NOW... HINT...if log (x) = y, then x = 10y PH, pOH & logs!

Acids and Bases Bundle 4: Water.

Acids and Bases Bundle 4: Water.

Calculations with Acids and Bases

Can you calculate for acids and bases?

pH Scale Definition of Acids and Bases

Unit 14 – Acid, Bases, & Salts

Unit 13 – Acid, Bases, & Salts

CHAPTER 19 NOTES: Part III: pH and [H+].

Ch. 15 & 16 - Acids & Bases II. pH (p ) C. Johannesson.

pH Calculations pH = -log[H+] 10-pH = [H+] pOH = -log[OH-]

Unit 13 – Acid, Bases, & Salts

pOH and [OH-] Calculations

Calculating pH (and pOH)

Unit 15 – Acid, Bases, & Salts

Unit 13 – Acid, Bases, & Salts

Unit 14 – Acid, Bases, & Salts

PH and pOH Acid Neutral Base.

Unit 5- lecture 5 Using the pH scale to characterize acids and bases.

Unit 13 – Acid, Bases, & Salts

DO NOW... HINT...if log (x) = y, then x = 10y

Ch. 14 & 15 - Acids & Bases II. pH.

Presentation transcript:

ION CONCENTRATIONS pH and pOH Calculations

 The pH scale is used to identify a substance as an acid or a base due to the pH value.  This scale is a measurement of the H + concentration, [H + ], in the solution.  The more H + in solution, the higher the concentration, the lower the pH.  The less H + in solution, the lower the concentraion, the higher the pH.  A pOH scale can also be thought of with the same mechanics.

 One solution has a [H + ] of 2.45x10 -3 and there is a second solution with a [H + ] of 1.24x Which solution would be the stronger acid?  The first solution has a larger [H + ] so it would have a lower pH and be the stronger acid. pH = -log[H + ] pH = -log(2.45x10 -3 ) = 2.61 pH = -log(1.24x ) = 9.91

 What is the pH of a substance that has a [OH - ] of 3.82x10 -8 ?  You will solve the pOH with the [OH - ]. Then pOH + pH = 14, so substract your answer from 14. pOH = -log[OH - ] pOH = -log(3.82x10 -8 ) = 7.42 pH + pOH = 14 pH = 14 – pOH pH = 14 – 7.42 = 6.58 You should not round until your final answer.

 When finding the [H + ] or [OH - ], you will use the antilog instead of the log. The antilog button is 10 x.  What is the [H + ] of a solution that has a pH of 8.92? [H + ] = 10 -pH [H + ] = = 1.20x10 -9 [H + ]  A solution has a pOH of 2.75 so it would have an [OH - ] of _______. [OH - ] = 10 -pOH [OH - ] = = 1.78x10 -3 [OH - ]