pH: Acid and Alkalis Flashcards
What is an acid?
Anything that produces hydrogen ions in a water solution
What is a base?
- Anything that produces hydroxide ions in a water solution
- Accepts H+ ions
What example of an acid?
HCl → H+ + Cl-
What some common acids?
Citrus fruits, aspirin, vitamin C Vinegar
What are some common bases?
Detergents, ammonia
based cleaners
What happens when you add acids to water?
The concentration of H3O+ ions increases
What is the formula for calculating pH?
𝑝𝐻 = −log_(10)[𝐻+]
What is H3O+?
Hydronium ion
How can the strength of a weak acid be expressed?
As an equilibrium
What is the pH of urine?
6
What is the pH of seawater?
8
What is the pH of stomach acid?
2
What does a high conc. of H+ ions lead to?
Higher pH (acidic)
What does a lower conc. of H+ ions lead to?
Lower pH (basic)
What are buffer solutions?
- Solutions that resist change to pH when small amounts of acid or base are added
- A chemical that accepts/releases H+ as necessary to keep pH constant
What do buffers usually consist of?
Normally consist of a weak acid and a salt (conjugate base) that provides additional A- ions
What does carbon dioxide in water produce?
- Carbonic acid
- Bicarbonate
- Carbonate
Why is CO2 important?
Because it forms weak acid solutions in water
What is Le Chatelier’s Principle?
If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium shifts to counteract the change to re-establish an equilibrium.
When was the river thames severly contaminated of cholera?
1850s
When was the ‘Great Stink’ of London?
1858
What was the solution the ‘Great Stink’?
Sewage drainage and pumping system
What are some water pollution from nutrients?
- Algal blooms
- Eutrophication
What is alkalinity?
- Refers to the ability of water to neutralise acid
- Water with high alkalinity has a high capacity to neutralise acid
