Acid – a compound that produces ions when dissolved in Examples: Vinegar – Lemon juice – ...

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Acid – a compound that produces ions when dissolved in Examples: Vinegar – Lemon juice – Tea – Ant venom –

Transcript of Acid – a compound that produces ions when dissolved in Examples: Vinegar – Lemon juice – ...

Acid – a compound that produces ions when dissolved in

Examples: Vinegar – Lemon juice – Tea – Ant venom –

taste Turns litmus paperReacts with metals to form gas solutions of acids are (must be mixed

with water!)Reacts with to form and

Sugar, corn syrup, modified corn starch, citric acid, tartaric acid, natural and artificial flavors, yellow 5, yellow 6, red 40, blue 1

What ingredients make these…

so sour?

H + one other elementBegin with Use the of the element

nameAdd the suffixHCl

HBr

HI

HF

H + polyatomic ionBegin with

ion without the

Add suffix if there was an Add suffix if there was an

HNO3

HClO3

H3PO3 H2CO3

acids – completely in water (create a lot of ) 3 binary acids

Ternary acidsStrong if # of atoms - # of atoms ≥

H2SO4 HNO3

acids – ionize only in

solution Binary acids – all others not listed above Ternary acids

Weak if # of atoms - # of atoms ≥

H3PO3 HNO2

Base – a compound that produces ions

when dissolved in

Examples: Milk of Magnesia – neutralizes

stomach acid

Drain cleaner–

taste Turns litmus paper solutions of bases

are (must be

mixed with water!)Reacts with to form

and

Use the same rules as for ions (name the cation, then name the anion)

NaOH

Ca(OH)2

KOH

bases – completely in water (create a lot of ions).

All hydroxides with groups and metals (except ).

bases - only

All bases not listed above as strong.

An acid must contain a and ionize in water to produce

An base must contain aand dissociates in water to produce

Only compounds with can be classified as a base. What about ammonia, ?

Can only be applied to reactions that occur in

Would classify some compounds as acids, such as

Classify each of the following as anArrhenius acid (A – acid) or base (A – base).

Ca(OH)2

HBr

H2SO4

LiOH

A Bronsted – Lowry is any substance that can a

A Bronsted – Lowry is any substance that can a

HCl + H2O H3O+ + Cl-

Let’s look at the reverse reaction.

Cl- + H3O+ H2O + HCl

acid – formed

when a

accepts a H+ from an acid.

base – a

that remains after an acid gives up a

H+.

Conjugate acid – base pair – 2 substances

related to each other by the

of a single H+.

Defined by how many H+ they can donate.

Type # of H+ donated

Example

Monoprotic 1 HNO3

Diprotic 2 H2SO4

Triprotic 3 H3PO3

Identify the acid, base, conjugate acid, and conjugate base.

HNO3 + H2O H3O+ + NO3-

Give the formula and name of the conjugate base of the following B-L acids.

(After the B-L acid donates a H+)

HI

HCO3-

Give the formula and name of the conjugate acids of the following B-L bases.

(After the B-L base accepts a H+)

H2PO4-

ClO3-

Water can sometimes act as a B-L acid and sometimes as a B-L base.

The of water:

H2O + H2O H3O+ + OH-

This reaction occurs to a very small

extent:

= = 1 x 10-7 M

[ ] means

[H+] x [OH-] =

relationship

Neutral

[H+] = [OH-

]Acidic [H+] > [OH-

]Basic [H+] < [OH-

]

[H+] are often small, so the pH scale is easier to use to represent acidity and basicity.

pH range is from to

log 102 =

log 10-3 =

In water, a solution,

= =

pH =

pH is < 7 Solution is acidic

pH is = 7 Solution is neutral

pH is > 7 Solution is basic

If [H3O+] = 1.0 x 10 –5 M, what is the pH?

Is the solution basic, neutral, or acidic?

If [H3O+] = 1.0 x 10 –12 M, what is the pH?

Is the solution basic, neutral, or acidic?

Given that a solution has a pH of 2.0, determine the [H3O+].

Similar to pH, there is also pOH.

Because [H+] x [OH-] =

[H+] 1pH 0 2pOH 14 10[OH-] 10-

14

10-8

Ex. battery acid

stomach acid

tomatoes

milk

[H+] 10-

12

pH 8 14pOH 4[OH-]

Ex. seawater

detergent

ammonia

oven cleaner

If [OH-] = 1.0 x 10 –10 M, what is the pOH?

What is the pH?

Is the solution basic, neutral, or acidic?

What is the pH and the pOH for 1.0 x 10 –6 M HF?

pH

pOH

Given that a solution has a pH of 9.0, determine the [OH -] and the pOH.

pOH

[OH -]

Acids LOSE H+ to become conjugate bases.

This is a H atom.

When a H+ is lost from an acid, this (-) electron remains.

The (+) proton is taken with the H.

+o

-

What is the conjugate base for the acid HBr?

HBr H+ + Br-

H Br

H Br+ -

Proton is keptby H.

Electron is leftby H.

Conjugate base

+

What is the conjugate base for the acid HNO2?

HNO2 H+ + NO2-

HNO

2

H+ -

Proton is keptby H.

Electron is leftby H.

Conjugate base

NO2

+

What is the conjugate base for the acid HSO3

-?

HSO3- H+ + SO3

2-

H SO3

H+ 2-

Proton is keptby H.

Electron is left by H (added to the one that was there already).

Conjugate base

SO3+

-

Bases GAIN H+ to become conjugate bases.

What is the conjugate acid for CN-?

CN- + H+ HCN

H CN++ -

H CN

The + and the – cancelout in the final molecule.

What is the conjugate acid for NH3?

NH3 + H+ NH4

+

H NH3

++

H

There is no – on the NH3 to cancelthe + from H, so the final moleculeis positive.NH

3

+

Review:

pH = [H+] =

pOH = [OH-] =

pH + pOH =

Example 1: Determine the pH of a 0.01 M HCl solution.

Example 2: Determine the pH of a 0.0010 M NaOH solution.

Example 3: Determine the pH of a 0.150 M KOH solution.

Example 4: Find [H3O+] for a solution that has a pH of 3.0.

Example 5: Find [H3O+] for a solution that has a pH of 8.2.

Example 6: Find [H3O+] and pOH for a solution that has a pH of 4.85.

Example 7: Find [OH-] for a solution that has a pH of 11.2.

What happens with you mix an acid with a base? A reaction

HCl + NaOH +

Products are always a ( and ) and

This is called a reaction

What happens with you mix an acid with a base? A ____________________________________________ reaction

Write the balanced chemical equation for the neutralization reaction between:nitric acid and potassium hydroxide

Write the balanced chemical equation for the neutralization reaction between:sulfuric acid and magnesium hydroxide

Neutralization reaction:

Titration – a process in which an acid-base neutralization reaction is used to determine the of a solution.

1. How many mL of 0.45 M HCl acid must be added to 25.0 mL of 1.00 M KOH to make a neutral solution?

2. What is the molarity of nitric acid if 15.0 mL of the solution is completely neutralized by 38.5 mL of 0.150 M NaOH?

3. A 25.0 mL solution of sulfuric acid is completely neutralized by 18 mL of 1.0 M LiOH. What is the concentration of the H2SO4 solution?