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2006-06-06 18:54:04 · 3 answers · asked by chha 1 in Science & Mathematics Chemistry

3 answers

It is NaOH. it is also known as lye or caustic soda. It is a caustic metallic base. It is widely used in industry, mostly as a strong chemical base in the manufacture of pulp and paper, textiles, drinking water, and detergents.

2006-06-06 19:00:35 · answer #1 · answered by Track Walker 6 · 0 0

forms ions in solution: Na+ and OH-
alkaline-basic

please clarify question more

sodium hydroxide is the chemical compound, NaOH, a white crystalline substance that readily absorbs carbon dioxide and moisture from the air. It is very soluble in water, alcohol, and glycerin. It is a caustic and a strong base (see acids and bases). Commonly known as caustic soda, lye, or sodium hydrate, it is available commercially in various solid forms, e.g., pellets, sticks, or chips, and in water solutions of various concentrations; both solid and liquid forms vary in purity. The major use of sodium hydroxide is as a chemical and in the manufacture of other chemicals; because it is inexpensive, it is widely used wherever a strong base is needed. It is also used in producing rayon and other textiles, in making paper, in etching aluminum, in making soaps and detergents, and in a wide variety of other uses. The principal method for its manufacture is electrolytic dissociation of sodium chloride; chlorine gas is a coproduct. Small amounts of sodium hydroxide are produced by the soda-lime process in which a concentrated solution of sodium carbonate (soda) is reacted with calcium hydroxide (slaked lime); calcium carbonate precipitates, leaving a sodium hydroxide solution.

2006-06-07 02:01:10 · answer #2 · answered by gopigirl 4 · 0 0

Chemical properties

Sodium hydroxide is completely ionic, containing sodium ions and hydroxide ions. The hydroxide ion makes sodium hydroxide a strong base which reacts with acids to form water and the corresponding salts, e.g., with hydrochloric acid, sodium chloride is formed:

NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

In general such reactions are represented by one simple net ionic equation:

OH−(aq) + H+(aq) → H2O

This type of reaction releases heat when a strong acid is used. Such acid-base reactions can also be used for titrations, and indeed this is a common way for measuring the concentration of acids. Related to this is the reaction of sodium hydroxide with acidic oxides. The reaction of carbon dioxide has already been mentioned, but other acidic oxides such as sulfur dioxide (SO2) also react completely. Such reactions are often used to "scrub" harmful acidic gases (like SO2) and prevent their release into the atmosphere.

2 NaOH + CO2 → Na2CO3 + H2O

Sodium hydroxide slowly reacts with glass to form sodium silicate, so glass joints and stopcocks exposed to NaOH have a tendency to "freeze". Flasks and glass-lined chemical reactors are damaged by long exposure to hot sodium hydroxide, and the glass becomes frosted. Sodium hydroxide does not attack iron or copper, but many other metals such as aluminium, zinc and titanium are attacked rapidly. In 1986 an aluminium road tanker in the UK was mistakenly used to transport 25% sodium hydroxide solution, causing pressurisation of the contents and damage to the tanker. For this same reason aluminium pans should never be cleaned with lye.

2 Al(s) + 6 NaOH(aq) → 3 H2 (g) + 2 Na3AlO3(aq)

Many non-metals also react with sodium hydroxide, giving salts. For example phosphorus forms sodium hypophosphite, while silicon gives sodium silicate.

Unlike NaOH, the hydroxides of most metals are insoluble, and therefore sodium hydroxide can be used to precipitate metal hydroxides. One such hydroxide is aluminium hydroxide, used as a gelatinous floc to filter out particulate matter in water treatment. Aluminium hydroxide is prepared at the treatment plant from aluminium sulfate by reaction with NaOH:

6 NaOH(aq) + Al2(SO4)3(aq) → 2 Al(OH)3(s) + 3 Na2SO4(aq)

Sodium hydroxide reacts readily with carboxylic acids to form their salts, and it is even a strong enough base to form salts with phenols. NaOH can also be used for the base-driven hydrolysis of esters (as is saponification), amides and alkyl halides. However, the limited solubility of NaOH in organic solvents means that the more soluble KOH is often preferred.

2006-06-07 02:01:18 · answer #3 · answered by Anonymous · 0 0

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