Strong acids and weak acids

Question 1

Acids produce ———- in water

Answer 1

protons

Acids ionise in aqueous solution = produce h+ ions
Example: HCL -> H^+ + NO2^-
HNO3 -> H^+ + NO3^-

Question 2

strong and weak acids in solution/water

Answer 2

strong acids ionise completely in water. All acid particles disassociate to produce H^+ Ions

Weak acids do not ionise completely in water. Only a small proportion of acid particles disassociate to produce H^+ Ions .

Question 3

The ionisation of a weak acid is a ..

Answer 3

reversible reaction, which sets up a equilibrium between the undissociated and the dissociated acid. Since only a few of the acid particles release H+, the position of equilibrium lies well to the left.

If concentration of H^+ ions is higher, the rate of reaction will be faster so strong acids will be more reactive than weak acids of the same concentration

Question 4

The pH of an acid or alkali is a measure of

Answer 4

concentration of H+ in the solution
For every decrease of pH by one, increase in concentration of H+ ion by factor of 10

So acid pH of 4 has 10x concentration of H+ ion of an acid that had pH of 5
For a decrease in pH of 2, concentration of H+ ion increase by a factor of 100

Factor H^+ ion concentration changes by = 10^-x

Question 5

What if too acids have same concentration ?

Answer 5

pH of strong acid is always less than pH of weaker acid

Question 6

What does acid strength tell you?

Answer 6

what proportion of the acid molecules ionise in water.
The concentration of an acid is different. Concentration measures how much acid there is a certain volume of water - how watered down your acid is

Question 7

Larger amount of acid there is in a certain volume of liquid, the more

Answer 7

concentrated the acid is
So you can have dilute ( not very concentrated) strong acid or concentrated weak acid.
pH will decrease with increasing acid concentration regardless of whether its a strong or weak acid