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Hydrogen peroxide is a chemical compound with the formula H 2 O 2.In its pure form, it is a very pale blue [5] liquid that is slightly more viscous than water.It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use.
Hydrogen peroxide works best as a propellant in extremely high concentrations (roughly over 70%). Although any concentration of peroxide will generate some hot gas (oxygen plus some steam), at concentrations above approximately 67%, the heat of decomposing hydrogen peroxide becomes large enough to completely vaporize all the liquid at standard pressure.
A typical mixture is 3 parts of concentrated sulfuric acid and 1 part of 30 wt. % hydrogen peroxide solution; [1] other protocols may use a 4:1 or even 7:1 mixture. A closely related mixture, sometimes called "base piranha", is a 5:1:1 mixture of water, ammonia solution (NH 4 OH, or NH 3 (aq)), and 30% hydrogen peroxide.
6 parts of deionized water; 1 part of aqueous HCl (hydrochloric acid, 37% by weight) 1 part of aqueous H 2 O 2 (hydrogen peroxide, 30%) at 75 or 80 °C, typically for 10 minutes. This treatment effectively removes the remaining traces of metallic (ionic) contaminants, some of which were introduced in the SC-1 cleaning step. [1]
The glass walls of the vessel adsorb water, and if any water leaks into the cell, the slow release of water into the titration solution can continue for a long time. Therefore, before measurement, it is necessary to carefully dry the vessel and run a 10–30-minute "dry run" in order to calculate the rate of drift.
C A is the analytical concentration of the acid and C H is the concentration the hydrogen ion that has been added to the solution. The self-dissociation of water is ignored. A quantity in square brackets, [X], represents the concentration of the chemical substance X. It is understood that the symbol H + stands for the hydrated hydronium ion.
The volume of such a mixture is slightly less than the sum of the volumes of the components. Thus, by the above definition, the term "40% alcohol by volume" refers to a mixture of 40 volume units of ethanol with enough water to make a final volume of 100 units, rather than a mixture of 40 units of ethanol with 60 units of water.
Reaction stoichiometry describes the 2:1:2 ratio of hydrogen, oxygen, and water molecules in the above equation. The molar ratio allows for conversion between moles of one substance and moles of another. For example, in the reaction 2 CH 3 OH + 3 O 2 → 2 CO 2 + 4 H 2 O. the amount of water that will be produced by the combustion of 0.27 moles ...