Properties of Acids and BasesGreen & Damjii – Chapter 8 – Section 2

Chang - Chapter 15

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Acids

Have a sour taste.

• Vinegar owes its taste to acetic acid: CH3COOH • Citrus fruits contain citric acid: C(CH2COOH)2(COOH)OH

4.3

Are corrosive.

• so don’t taste them!

Acids

Have a pH < 7, and interact with indicators…

• Litmus

• Phenolpthalein

• Universal Indicator Soln

4.3http://depts.uwc.edu/chemistry/helpful_files/indicators.jpg

Acids

React with active* metals to produce hydrogen gas.

4.3

active* metals are those above H+ in the reactivity series – see p. 246.

Ex1: magnesium + hydrochloric acid

Ex 2: magnesium + sulfuric acid

AcidsReact with active* metals to produce hydrogen gas.

4.3

active* metals are those above H+ in the reactivity series – see p. 246.

http://cathodic--protection.blogspot.com/2009/08/fundamental-of-corrosion.html

AcidsReact with base (metal oxide or metal hydroxide) to produce a salt and water.

4.3

Ex 3: nitric acid + copper(ll) oxide

Ex 4: phosphoric acid + sodium hydroxide

Acids

React with metal carbonates and hydrogen carbonates to produce a salt, water, and carbon dioxide gas

4.3

Ex 5: hydrochloric acid reacts with zinc carbonate:

Ex 6: ethanoic acid reacts with sodium hydrogen carbonate:

Common Acids (memorize)

hydrochloric acid HClsulfuric acid H2SO4nitric acid HNO3

ethanoic (or acetic) acid CH3COOHwater H2Ohydrofluoric acid HFphosphoric acid H3PO4

Solutions of bases are called alkalis…• bitter taste• feel slippery

Many soaps contain bases.

Bases

4.3

? Any substance that neutralizes an acid ?• metal oxides • metal hydroxides• metal carbonates• ammonia• amines

Bases

Have a pH > 7, and interact with indicators…

• Litmus

• Phenolpthalein

• Universal Indicator Soln

4.3http://depts.uwc.edu/chemistry/helpful_files/indicators.jpg

Bases

React with acids to produce a salt and water

4.3

Ex 7: calcium oxide reacts with hydrochloric acid:

Ex 8: calcium hydroxide reacts with nitric acid:

Common Bases(memorize)

sodium hydroxide NaOHpotassium hydroxide KOHbarium hydroxide Ba(OH)2

ammonia NH3

water H2Oethyl amine CH3 CH2NH2

ammonium hydroxide NH4OH 

Textwork…

Read Section 8.2 - P 212• Properties of Acids and Bases

Do Ex 8.2 p 212 # 1, 2, 3a-f