Search results
Results from the WOW.Com Content Network
The strength of an inorganic acid is dependent on the oxidation state for the atom to which the proton may be attached. Acid strength is solvent-dependent. Acid strength is solvent-dependent. For example, hydrogen chloride is a strong acid in aqueous solution, but is a weak acid when dissolved in glacial acetic acid .
Sulfuric acid is a colorless oily liquid, and has a vapor pressure of <0.001 mmHg at 25 °C and 1 mmHg at 145.8 °C, [16] and 98% sulfuric acid has a vapor pressure of <1 mmHg at 40 °C. [17] In the solid state, sulfuric acid is a molecular solid that forms monoclinic crystals with nearly trigonal lattice parameters.
Sulfuric(IV) acid (United Kingdom spelling: sulphuric(IV) acid), also known as sulfurous (UK: sulphurous) acid and thionic acid, [citation needed] is the chemical compound with the formula H 2 SO 3. Raman spectra of solutions of sulfur dioxide in water show only signals due to the SO 2 molecule and the bisulfite ion, HSO − 3 . [ 2 ]
However, SO 3 added to concentrated sulfuric acid readily dissolves, forming oleum which can then be diluted with water to produce additional concentrated sulfuric acid. [4] Typically, above concentrations of 98.3%, sulfuric acid will undergo a spontaneous decomposition into sulfur trioxide and water H 2 SO 4 ⇌ SO 3 + H 2 O
If dilute acid is not used, the early precipitation of 4th group cations (if present in solution) may occur, thus leading to misleading results. Acids beside HCl are rarely used. Sulfuric acid may lead to the precipitation of the 5th group cations, whereas nitric acid oxidises the sulfide ion in the reagent, forming colloidal sulfur.
Concentrated sulfuric acid is a strong dehydrating agent that can strip available water molecules and water components from sugar and organic tissue. [ 141 ] The burning of coal and/or petroleum by industry and power plants generates sulfur dioxide (SO 2 ) that reacts with atmospheric water and oxygen to produce sulfurous acid (H 2 SO 3 ). [ 142 ]
Commonly used mineral acids are sulfuric acid (H 2 SO 4), hydrochloric acid (HCl) and nitric acid (HNO 3); these are also known as bench acids. [1] Mineral acids range from superacids (such as perchloric acid) to very weak ones (such as boric acid). Mineral acids tend to be very soluble in water and insoluble in organic solvents.
The second part of the Winkler test reduces (acidifies) the solution. The precipitate will dissolve back into solution as the H + reacts with the O 2− and OH − to form water. MnO(OH) 2 (s) + 4 H + (aq) → Mn 4+ (aq) + 3 H 2 O(l) The acid facilitates the conversion by the brown, Manganese-containing precipitate of the Iodide ion into ...