Acid and Bases continued

Acids reacting with Metals

• Acids react with metals to produce hydrogen gas

Acid + metal hydrogen gas + _______

ExampleHydrochloric acid + zinc hydrogen gas + zinc chloride

HCl (aq) + Zn (s) H2(g) + ZCl2 (aq)

Acids reacting with carbonates

• When acids react with carbonate compounds they produce carbon dioxide gas.

acid + carbonate carbon dioxide + ___ + ____

Example: vinegar reacting with baking soda +

Acetic acid + sodium hydrogen carbonate carbon dioxide + water + sodium acetate

HC2H3O2 (aq) + NaHCO3 (aq) CO2(g) + H2O (l) + NaC2H3O2 (aq)

Chemical Formulas of Acids

• All acids release at least one hydrogen ion (H+)• These H+ ions give acids their properties• Chemical formulas of acids begin with an H• Chemical formulas of acids always have “(aq)” – Acids ONLY SHOW PROPERTIES WHEN DISSOLVED

IN WATER

• Examples HCl (aq) HBr (aq) HF (aq) H2S (aq)

Names of Acids

• Binary Acids– Contain only 2 elements (hence Bi-nary)– Example: H2S (aq) is hydrosulfuric acid

• Oxyacids (related to polyatomic ions) – Same as the related polyatomic ion, but with

additional hydrogen ions – Example: phosphoric acid contains phosphate and

3 hydrogen ions H3PO4

Names of Acids Binary Acids Oxyacids

Acid Name

Chemical Formula

HF (aq) hydrofluoric acid

HCl (aq) hydrochloric acid

HBr (aq) hydrobromic acid

H2S (aq) hydrosulfuric acid

Acid Name Chemical Formula

HC2H3O2 (aq) Acetic acid

HNO3 (aq) Nitric acid

H2CO3 (aq) Carbonic acid

H2SO4 (aq) Sulfuric acid

H3PO4 (aq) Phosphoric acid

Chemical properties of bases

• Completely separates into its ions as it dissolves in water

• NaOH (s) dissolve in water Na+ (aq) + OH- (aq)• Releases hydroxide OH- ions when dissolved

Chemical formulas and names of basesBase Chemical Formula

Sodium hydroxide NaOH (aq)

Calcium hydroxide Ca(OH)2 (aq)

Ammonium hydroxide NH4OH (aq)

Magnesium hydroxide Mg(OH)2 (aq)

Aluminum hydroxide Al(OH)3 (aq)

Sodium hydrogen carbonate(baking soda)

NAHCO3 (aq)

Acid-Base indicators

Indicator Colour in Acid

Colour in Base

Bromothymol blue Yellow Blue

Phenolphthalein Colourless Pink

Phenol red Yellow Red/pink

Litmus Red Blue

Methyl orange Red Orange/yellow

The pH Scale• Stands for the power of Hydrogen• Measure of hydrogen ion (H+) concentrations• More hydrogen ions (H+), more acidic• THEN WHY ARE ACIDS a Lower number!??!?!

pH 1 pH 2 pH 3… pH 10 pH 13 pH 14

0.1 0.01 0.001 0.0000000001 0.0000000000001 0.00000000000001

pH Scale

neutral

Acids + Bases

• When an acid and base are combined they react in a __________________ reaction.

• Acids donate ______ cations• Bases donate ________ anions

• ________________ is this type of reaction ________________.

Acids + Bases

acid + base water + ionic compound

For example…HCl(aq) + KOH(aq) H2O(l) + KCl(aq)

Why is this important?

• Treating chemical spills– 150’000 L of sulfuric acid in Englehart, Ontario. 2007. – Treated with calcium oxide

Why is this important?

• Medicine– Stomach antacids

Acids and metals

• When an acid reacts with a metal, it produces a compound with the cation of the metal and the anion of the acid, and hydrogen gas.

• Ex.Hydrochloric acid + zinc hydrogen gas + zinc chloride