BrnstedLowry theory of acids and bases

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Brønsted-Lowry theory of acids and bases
H Cl- NH3 Cl- NH4
An acid is a H donor HCl A base is a H
acceptor NH3
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acids and bases in solution
HCl H (aq) Cl- (aq)
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Alkalis vs bases
A base is a H acceptor An alkali is a base
that dissolves in water to form hydroxide
ions. All alkalis are bases not all bases are
alkalis!
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Questions
Chemical Ideas page 194 Question 2 d,g,h 3
b,c (extension complete remaining parts of 2
3)
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Acid-base pairs
An acid exists in solution in equilibrium
Overall we call this a conjugate acid-base pair
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Acid-base pairs
Water can act as an acid OR a base
Proton donor
Proton acceptor
We say water is amphoteric
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Questions
Chemical Ideas page 194 Question 4b
5b (extension complete remaining parts of 4
5)
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Strength of acids and bases
A strong acid donates protons easily.
A weak acid donates protons less easily,
however the conjugate base accepts protons more
easily than a strong acid
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Acid-base Indicators
Acid base indicators are coloured organic
substances that are weak acids. For example
Litmus
acid
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Acid-base Indicators
Acid base indicators are coloured organic
substances that are weak acids. For example
Litmus
acid