Acids and Bases

Milk contains lactic acid, which is produced when bacteria ferment lactose (milk sugar). Fresh milk contains very little lactic acid, but it increases as milk sours or ferments into products like yogurt. Oxalic acid is found in spinach, citric acid in citrus fruits, and boric acid is not naturally found in food.

Carbonic acid (H2CO3) is responsible for carbonation in soft drinks. When CO2 dissolves in water under pressure, it forms carbonic acid, which creates the 'fizz' and tingling sensation. Citric acid adds flavor but not fizz, acetic acid is in vinegar, and oxalic acid is toxic.

Sulfuric acid (H2SO4) is historically known as 'Oil of Vitriol.' The term 'vitriol' refers to sulfate salts, and sulfuric acid was the most important. Hydrochloric acid is 'muriatic acid,' and neither hydroiodic nor nitric acid have this common name.

Vinegar is very dilute acetic acid (typically 4-8% acetic acid in water). Citric acid is in citrus fruits, carbonic acid is in carbonated water, and phosphoric acid is in some dark sodas but not vinegar.

Sulfuric acid is used in lead-acid car batteries as the electrolyte. When the battery discharges, it reacts with lead plates to form lead sulfate. Hydrochloric and nitric acids are too corrosive and reactive for this use, and phosphoric acid is used in some rust removal but not standard car batteries.

Nitric acid has the formula HNO3, containing one hydrogen, one nitrogen, and three oxygen atoms. H2SO4 is sulfuric acid, CO is carbon monoxide, and CH4 is methane.

Phosphoric acid in colas has a pH around 2.5-3.5, making it quite acidic. While experiments show it can corrode materials like nails over time, the '4 days' claim may be exaggerated or dependent on specific conditions - the key point is that cola phosphoric acid is strongly corrosive.

Acids exhibit all these properties: they produce H+ or H3O+ ions in water, taste sour, and neutralize bases through acid-base reactions.

Weak acids partially dissociate in water, establishing equilibrium between mostly undissociated molecules and few ions. Strong acids (like HCl) ionize completely.

Sodium hydroxide (NaOH) is a metal hydroxide that dissociates completely in water to produce hydroxide ions (OH-), which is the defining characteristic of a base. It is a strong alkali used in many industrial processes.

Aspirin's chemical name is acetylsalicylic acid (ASA). It is synthesized by acetylating salicylic acid, which is derived from willow bark. Borax is sodium borate, carbonic acid is H2CO3, and salicylic acid is the precursor compound, not aspirin itself. The acetyl group (CH3CO) is what makes it aspirin, improving its efficacy and reducing side effects compared to salicylic acid.

Lead-acid car batteries use sulfuric acid (H2SO4) as the electrolyte solution. Hydrochloric acid is used in cleaning and industrial processes, nitric acid in fertilizer production. 'Sulphuric' is the correct spelling.

Citric acid (C6H8O7) is a naturally occurring organic acid found abundantly in citrus fruits like lemons, oranges, limes, and grapefruit, giving them their characteristic sour taste. Sulphuric acid is a strong mineral acid, acetic acid is found in vinegar, and amino acids are protein building blocks.

Hydrofluoric acid (HF) is the only common acid capable of dissolving glass. It reacts with silicon dioxide (SiO₂), the main component of glass, forming silicon tetrafluoride and water. Hydrochloric, nitric, and sulfuric acids do not react with glass.

Hydrochloric acid has the chemical formula HCl, formed from hydrogen (H) and chlorine (Cl). It's a strong acid found in gastric juice and used industrially. NaOH is sodium hydroxide (a base), AgBr is silver bromide, and KBr is potassium bromide.