Table of Contents
Acid, Base, Salt
back to Chemistry $$\require{mhchem}$$ Base = Alkali or Alkaline
| Acid | Neutral | Base |
|---|---|---|
| pH < 7 | pH = 7 | pH > 7 |
| turns litmus red | turns litmus blue | |
| $\ce{H+}$ ions | $\ce{OH-}$ ions | |
| sour taste | bitter taste | |
| sticky | slippery | |
| proton donor | proton acceptor |
proton = hydrogen anion $\ce{H+}$
However, they have this low pH values since acids give high amounts of H+ ions to the aqueous solution and pH is the logarithm of the inverse of H+ concentration
Acid
Two definitions
- Bronsted-Lowry
- Lewis
Bronsted-Lowry
hydrochloric acid
hydrogen having a covalent bond with chlorine
water can act as acid or as base
conjugate base
conjugate acid
Two types:
- a moledule capable of donating a proton
- a molecule capable of forming a covalent bond with an electron pair
Characteristics:
Common acids:
- carbonated water
- aspirin
- hydrochloric acid
- citric acid
Base
Lime: acid or base?
Lime juice squeezed from the fruit is an acid. A citric acid. Drinking water infused with lime juice might be referred to as “lime water” (two words).
Lime, a white powder made from pulverized limestone, is a base. It is usually composed of calcium oxide $\ce{CaO}$ and/or calcium hydroxide $\ce{Ca(OH)2}$. It is used in agriculture and construction and is sometimes sold commercially as “barn lime”, “quick lime”, or “garden lime”. Limewater (one word) is the common name for a saturated aqueous solution of calcium hydroxide $\ce{Ca(OH)2}$.
Salt
A chemical compound consisting of an ionic assembly of cations and anions.
$\ce{NaCl}$ sodium chloride
$\ce{Na}$ sodium
$\ce{Cl}$ chlorine
$\ce{Cl}$ chlorine is the element with atomic number 17, in period 3 with 1 electron short of argon.
$\ce{Cl-}$ chloride is the negative ion of chlorine with one extra electron added, when joined to another element in a compound
$\ce{NaCl}$ sodium chloride $\ce{KCl}$ potassium chloride $\ce{CaCl}$ calcium chloride