Acids and Bases Flashcards
What makes an acid an acid?
When mixed with water, all acids release hydrogen ions (H+). They produce H+ ions in an aqueous solution i.e they’re proton donors.
It has a pH of less than 7.
What makes a base a base?
They do the opposite of acids- they want to grab H+ ions.They remove H+ ions from an aqueous solution i.e they’re proton acceptors.
It is a substance with a pH greater than 7.
What is the general formula for an acid base reaction?
Acid + base –> Salt + water
What is the equation for the reaction between metal oxides and acids?
Metal oxide + acid –> salt + water
What is the general for the reaction between a metal hydroxide and an acid?
Metal hydroxide + acid –> salt + water
What is the equation for the reaction of acids with metals?
Metal + acid –> metal salt + hydrogen
What is the equation for the reaction of acids with carbonates?
Metal carbonate + acid –> metal salt + carbon dioxide + water
What are strong acids?
Strong acids dissociate/ionise almost completely in water- nearly all the H+ ions will be released.
What are strong bases?
Strong bases ionise almost completely in water too.
What are weak acids?
Dissociate only very slightly in water- so only small numbers of H+ ions are formed- the equilibrium lies well over to the left.
What are weak bases?
Only slightly ionise in water- the equilibrium lies well over to the left.
What are alkalis?
Bases that dissolve in water.
What is a conjugate pair?
Two molecular species that easily transfer a hydrogen ion between them, especially from the acid to the base.
What is the pH scale a measure of?
Hydrogen ion concentration.
How can you work out pH from hydrogen ion concentration?
-log10( x )
The ionic product of water Kw is…
…always the same at a certain temperature.
1 x 10-14
How can you work out Kw?
Multiply Kc by [H2O]
What are the units of Kw?
mol2dm-6
What does monobasic mean?
One mole of acid produces one mole of hydrogen ions.
What is a buffer?
A solution that resists changes in pH when small amounts of acids or alkali are added.
Describe, in terms of equilibrium, how strong and weak acids differ in the way they dissolve in water.
Strong: equilibriumt is far to the left.
Weak: equilibrium is far to the right.
Explain how the choice of the indicator is linked to the pH curve.
pH range (of the indicator) matches vertical section/rapid pH change
