Day 13– Naming Acids & Bases

Sci 10 Chemistry

What is an Acid?

Acid: a compound that makes hydrogen ions H+

(aq) when dissolved in water i.e.: HCl (aq) → H+

(aq) + Cl- (aq)

Note: acids must be dissolved in water to produce H+ ions. Look for the (aq) which means aqueous to indicate the acid is dissolved in water

How to identify them:

Hydrogen + a non-metal with the (aq) symbol

What is a Base?

Base: a compound that makes hydroxide ions OH- (aq) when dissolved in water i.e. NaOH (aq) → Na+ (aq) + OH- (aq)

How to identify them:

Metal + hydroxide ion (OH) with the (aq) symbol

Naming Bases

Easy! Name the cation followed by the anion (hydroxide) with the ending –ide (just like we’ve been doing all along with ionic compounds)

You will know that it is a base if you see the (aq) i.e. NaOH (aq)

sodium hydroxide

i.e. Ca(OH)2 (aq)

calcium hydroxide

Try It!

Name the following base:

1. KOH (aq)

potassium hydroxide

Naming Acids with A Non-Metal (simple anions)

i.e. HCl (aq)

You will know to name this as an acid because of the (aq)

1. Write “hydro-”

2. Add the name of the non-metal (shortened, with the ending “-ic”) i.e. chloric

3. Add the second word “acid”

HCl (aq) = hydrochloric acid

Try It!

Name the following acids: HF (aq)

hydrofluoric acid

HBr (aq)

hydrobromic acid

HI (aq)

hydroiodic acid

Naming Acids with Polyatomic Ions

The first part of the name is the name of the polyatomic ion which is shortened . One of two endings are added to this name. - ic if the anion name ends in - ate. - ous if the anion name ends in - ite.

The last part of the name is acid i.e. HNO3(aq) (nitrate ion) = nitric acid

i.e. HNO2(aq) (nitrite ion) = nitrous acid

Try It!

Name the following acids: H2CO3 (aq)

carbonic acid

H2SO4 (aq)

sulfuric acid (sulfate ion)

H2SO3 (aq)

sulfurous acid (sulfite ion)

Name to Formula Determine the anion present from the name:

“hydro” in the name means H plus a non-metal “-ic” or “-ous” means H plus a polyatomic ion

The cation (positive ion) is always H + Write down the formulas of the two ions. Draw the table to see

which subscripts to add: i.e. sulfuric acid sulfuric ------> sulfate --------> SO4 2- acid -------> hydrogen --------> H 1+ H SO4

1+ 2-

Formula -------> H2SO4 (aq)

Try It!

Write the formula for:

phosphoric acid

Anion = phosphate PO43-, Cation = H 1+

H PO4

1+ 3-

1+

1+

Formula: H3PO4(aq)

To Do

Day 13 Practice

p. 165 #18, 20