Acids and bases

1. ACIDS AND BASES

3. • Properties: (other than tasting sour and being corrosive)
1) React with metals
2) React with carbonates
3) Conduct electricity
4) Turn blue litmus paper red
5) Neutralize bases
ACIDS ARE CORROSIVE
ACIDS

4. If you swallowed a penny, what would happen?
(DON’T TRY THIS AT HOME!!!)
1) ACIDS REACT WITH METALS

5. 2HCl(aq) + Zn(s)  H2(g) + ZnCl2(aq)
1) ACIDS REACT WITH METALS

6. What happens when you put baking soda (sodium
bicarbonate) into vinegar?
HC2H3O2(aq) + NaHCO3(aq)  CO2(g) + H2O(l) + NaC2H3O2(aq)
2) ACIDS REACT WITH CARBONATES

7. Acids are made of ions, so in water these ions separate
and can conduct electricity
HCl(aq)  H+
(aq) + Cl-
(aq)
Hydrogen ion is what
makes an acid acidic
3) ACIDS CONDUCT ELECTRICITY

8. H+
Cl-
H+
Cl-
H+
Cl-
Strong acids
ionize completely
in water, while
weak acids only
ionize slightly
3) ACIDS CONDUCT ELECTRICITY

9. NEGATIVELY-CHARGEDELECTRODE
POSITIVELY-CHARGEDELECTRODE
H+
Cl-
H+Cl-
H+
Cl-
H+
Cl-
- +
3) ACIDS CONDUCT ELECTRICITY

10. Blue litmus paper is an indicator and turns red when it
touches acid
4) ACIDS TURN BLUE LITMUS PAPER RED

11. Acids can neutralize bases, so adding an acid to a base
can neutralize their caustic nature
HCl(aq) + NaOH(aq)  H2O(l) + NaCl(aq)
Hydrochloric acid + sodium hydroxide  water + salt (sodium chloride)
Corrosive + caustic  non-corrosive + non-corrosive
5) ACIDS NEUTRALIZE BASES

12. Properties: (other than tasting bitter, feeling slippery)
1) Conduct electricity
2) Turn red litmus paper blue
3) Turns phenolphthalein pink
4) Neutralize acids
BASES ARE CAUSTIC
BASES

13. Bases are made of ions, so in water these ions separate
and can conduct electricity
NaOH(aq)  Na+
(aq) + OH-
(aq)
hydroxide ion makes
bases basic
1) BASES CONDUCT ELECTRICITY

14. Red litmus paper is an indicator and turns blue when it
touches base
2) BASES TURN RED LITMUS PAPER BLUE

15. Phenolphtalein is colourless, and turns pink in bases
(above pH 8.2) while remaining colourless in acids.
3) BASES TURN PHENOLPHTALEIN PINK

16. Bases can neutralize acids, so adding a base to an acid can eliminate their
corrosiveness
Example: Antacids to neutralize stomach acid
2HCl(aq) + CaCO3(aq)  CaCl2(aq) + H2CO3(aq)
H2CO3(aq)  H2O(l) + CO2(g)
4) BASES NEUTRALIZE ACIDS

17. ACIDS:
1) Non-metal + oxygen  non-metal oxide
2) Non-metal oxide + water  ACID!
EXAMPLE:
N2 + 2O2  2NO2
NO2 + H2O  HNO3
BASES:
1) Metal + oxygen  Metal oxide
2) Metal oxide + water  BASE!
EXAMPLE:
2Mg + O2  2MgO
MgO + H2O  Mg(OH)2
HOW TO MAKE ACIDS AND BASES

18. Indicators change color depending on whether a substance is
acidic or basic
ACID-BASE INDICATORS

19. Different indicators change colour at specific pH ranges
ACID-BASE INDICATORS

20. The strength of an acid or base is measured with pH
pH
power hydrogen
pH = power of hydrogen
pH

21. Calculating pH
Logarithm with base 10 Concentration of
hydrogen ions
pH = -log [H+]
pH

22. At 25°C: From 0 to 14, with 7 being NEUTRAL
pH < 7  acidic
pH = 7  neutral
pH > 7  basic
pH SCALE

23. pH SCALE

24. Every pH level is 10x more concentrated than the level
above.
i.e. pH 4 is 10x more concentrated than pH 5
pH 3 is 100x more concentrated than pH 5
pH SCALE

25. Polyatomic ion
name
Acid anion name Example
sulfate sulfuric H2SO4 sulfuric acid
chlorate chloric HClO3 chloric acid
carbonate carbonic H2CO3 carbonic acid
phosphate phosphoric H3PO4 phosphoric acid
Recall: Polyatomic ions have modified names in acids
ACID NAMING

26. H2SO4(aq)
Sulfuric acid
OXYACID
Recall: Most acids have hydrogen
HCl(aq)
Hydrochloric acid
BINARY ACID
1) Naming:
ACID NAMING

27. bromic acid
BrO3H
1 1+ -
= HBrO3(aq)
2) Writing the chemical formula:
ACID NAMING

28. Polyatomic ion
name
Acid anion name Example
sulfite sulfurous H2SO3 sulfurous acid
chlorite chlorous HClO2 chlorous acid
carbonite carbonous H2CO2 carbonous acid
phosphite phosphorous H3PO3 phosphorous acid
Oxyacids with polyatomic ions that end in “ite” are
given the ending “ous”
ACID NAMING

29. HNO2(aq)
1) Naming:
nitrite
= nitrous acid
ACID NAMING

30. bromous acid
BrO2H
1 1+ -
= HBrO2(aq)
2) Writing the chemical formula:
ACID NAMING

31. HOMEWORK
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