Good Day 04/21/23Good Day 04/21/23

•Starter: What do you know about acids?

•Today we will be –starting our brief discussion of acids and bases.

•Starter: What do you know about acids?

•Today we will be –starting our brief discussion of acids and bases.

Now what is a base? Is it simply the thing you run to in baseball or is there

more?

Now what is a base? Is it simply the thing you run to in baseball or is there

more?•A Base is the opposite of an

acid.•Acids are dangerous because

they want to put a hydrogen ion on you, bases want to take a hydrogen off of you.

•A Base is the opposite of an acid.

•Acids are dangerous because they want to put a hydrogen ion on you, bases want to take a hydrogen off of you.

Which of the following is worse for you to

swallow?

Which of the following is worse for you to

swallow?•Phosphoric Acid•Sodium Hydroxide

•Phosphoric Acid•Sodium Hydroxide

Perhaps a surprisePerhaps a surprise•Phosphoric Acid is a main ingredient in Coca-Cola (that doesn’t mean it is safe :)

•Sodium Hydroxide is the 2nd ingredient in Liquid Plumber!

•Phosphoric Acid is a main ingredient in Coca-Cola (that doesn’t mean it is safe :)

•Sodium Hydroxide is the 2nd ingredient in Liquid Plumber!

Many cleaners

are bases and

ridiculously

dangerous

Many cleaners

are bases and

ridiculously

dangerous

Why is that we seem to only know about acids?Why is that we seem to only know about acids?

•Movies often use “acid” to eat through metal or throw it on the bad guy to make him dissolve.

•Most people know that acids can burn and cause harm but not too many know about the dangers of bases.

•Movies often use “acid” to eat through metal or throw it on the bad guy to make him dissolve.

•Most people know that acids can burn and cause harm but not too many know about the dangers of bases.

What these acids have in common? And the bases?What these acids have in common? And the bases?

Acids Bases

HCl – Hydrochloric Acid

NaOH – Sodium Hydroxide

H2SO4 – Sulfuric Acid

Mg(OH)2 – Magnesium Hydroxide

HNO3 – Nitric Acid Ca(OH)2 – Calcium Hydroxide

Yep you figured it out, Acids are all about the

Hydrogen and the bases all have the Hydroxide ion

(OH).

Yep you figured it out, Acids are all about the

Hydrogen and the bases all have the Hydroxide ion

(OH).• There are some acids that don’t

have Hydrogen, and some bases without hydroxide, but we’ll be discuss those on another day.

• There are some acids that don’t have Hydrogen, and some bases without hydroxide, but we’ll be discuss those on another day.

Na(OH) plus HCl equals

Salt Water

(OH)-(OH)-

(OH)-

Properties of Acids and Bases

Properties of Acids and Bases

•Litmus is an indicator, it changes color when it comes in contact with an acid or a base. (remember blue=base)

•Litmus is an indicator, it changes color when it comes in contact with an acid or a base. (remember blue=base)

Acids and bases have many uses around the home and in

industry.

Acids and bases have many uses around the home and in

industry.

Acids and bases have many uses around the home and in

industry.

Acids and bases have many uses around the home and in

industry.

Question

Summary of Answer

What is an

acid?

An acid is a substance that tastes sour, reacts with metals and carbonates, and turns blue litmus paper red.

What is a base?

A base is a substance that tastes bitter, feels slippery, and turns red litmus paper blue.

What are uses of

acids and bases?

Uses of acids include cleaning products, fertilizers, and car batteries; uses of bases include cleaning products, baking ingredients, and cement manufacturing.

The table lists some commonly encountered

acids and bases.

The table lists some commonly encountered

acids and bases.

NH3 + H2O NH4OHNH3 + H2O NH4OH

The pH ScaleThe pH Scale

• pH is a measure of the concentration of Hydrogen ions in a solution.

• A pH of 14 means that there are 1x10-14 H+ Ions.

• We use the logorithim of the concentration because it is easier to use.

• pH is a measure of the concentration of Hydrogen ions in a solution.

• A pH of 14 means that there are 1x10-14 H+ Ions.

• We use the logorithim of the concentration because it is easier to use.

The pH ScaleThe pH Scale

•A low pH tells you that the concentration of hydrogen ions is high.

•A low pH tells you that the concentration of hydrogen ions is high.

The pH ScaleThe pH Scale

•In contrast, a high pH tells you that the concentration of hydrogen ions is low.

•In contrast, a high pH tells you that the concentration of hydrogen ions is low.

Acid-Base ReactionsAcid-Base Reactions•A reaction between an acid and a base is called neutralization. An acid-base mixture is not as acidic or basic as the individual starting solutions.

•A reaction between an acid and a base is called neutralization. An acid-base mixture is not as acidic or basic as the individual starting solutions.

Acid-Base ReactionsAcid-Base Reactions

•Each salt listed in this table can be formed by the reaction between an acid and a base.

•Each salt listed in this table can be formed by the reaction between an acid and a base.

Previewing VisualsPreviewing Visuals

Q. What is a neutral solution?

A. A neutral solution is one that has a pH close to 7.

Q. What is neutralization?

A. Neutralization is a reaction between an acid and a base.

Video LinksVideo Links

•Link to Acid Base demos