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# Examples of Hydrated Salts

Acids and bases when react together, neutralize each other to produce salt and water. However, they mostly react in an aqueous solution. An aqueous solution is a solution where the solvent is usually water. Acids produce hydrogen ions in solution. Most acids have the general formula HA, where A minus is an anion, which are negatively-charged ions. Bases produce hydroxide ions in solution. Most bases have the form BOH, where B plus is a cation, which are positively-charged ions. Neutralization happens because hydrogen ions and hydroxide ions react to produce water.

The anion of acid and the cation of base then react to form a salt. For example, hydrochloric acid and sodium hydroxide neutralize each other to form the salt sodium chloride and water. Similarly, sulphuric acid and ammonium hydroxide neutralize to form a salt ammonium sulphate and water. Another example is the reaction of black copper oxide and acetic acid in the vinegar, to form copper acetate and water. The copper acetate is water soluble and dissolves away, leaving a clean copper metal surface. However, when exposed to air this copper acetate reacts with the oxygen in the air to form blue-green copper carbonate.

All non-metal oxides are acidic in nature and react with water to form acids and they react with bases to form salts. For example sulphur trioxide reacting with barium hydroxide to give the salt barium sulphate and water.

Another example is reaction of phosphorus pentoxide with sodium hydroxide to form sodium phosphate and water. Most non-metal oxides are acidic and form oxy-acids, which in turn yield hydronium ions (H3O+) in aqueous solution. Some of the salts contain water in their crystal. This water content is called as water of crystallisation and such salts are called as hydrated salts. You know that the formula of gypsum CaSO4. 2H2O and formula for plaster of Paris is CaSO4. $\frac{1}{2}$H2O.

What do you think about water molecules shown in formula?  Why we wrote it just next to main formula separated by dot? This is known as water of crystallization. It indicates the number of water molecules which are chemically combined with the salt in its crystalline state. These water molecules combine in a definite molecular proportion. The presence of water in the molecule affects the geometry of crystal and other physical properties such as colour, melting point etc.

Such type of salts is known as hydrous salts. These salts are better known with their common names instead of their chemical names. Some common hydrous or hydrated salts with their common name are as given below;

 Name Chemical Formula Common Name Barium Chloride BaCl2.2H2O Calcium Chloride CaCl2, 6H2O Dow flake Calcium Nitrate Ca(NO2)2.4H2O Lime salt petre or Norwegian salt petre Calcium Sulphate CaSO4 .2H2O Gypsum Calcium Sulphate Hemi Hydrate (CaSO4)2.H2O Plaster of Paris Copper (II) Chloride CuCl2. 2H2O Copper (II) Sulphate CuSO4,5H2O Blue vitriol Ferrous Sulphate FeSO4.7H2O Green vitriol Magnesium Sulphate MgSO4.7H2O Epsom salt Potassium Aluminium Sulphate K2SO4.Al2 (SO4)3.24H2O Potash alum Sodium Carbonate Deca Hydrate Na2CO3, 10 H2O Washing soda (crystal) Sodium Carbonate Mono Hydrate Na2CO3. H2O Washing soda (powder) Sodium Sulphate Na2SO4. 10H2O Glauber's Salt Zinc Sulphate ZnSO4.7H2O White vitriol

From Wikipedia

Garlic salt

Garlic salt is a flavored salt used as food seasoning made of a mixture of dried ground garlic and table salt with an anti-caking agent (e.g. calcium silicate). In its most basic form it is made by combining 3 parts salt and 1 part garlic powder.

It is used as a substitute for fresh garlic, for example in burgers or chili.

It should not be mistaken with minced garlic, granulated garlic, or garlic powder, which are just ground dried garlic, also sold as spices.

Ground garlic can be made into garlic salt by pouring it into a bowl with salt and pouring humectant on it.

Acid salt

Acid salt is a somewhat obscure term for a class of salts formed by the partial neutralization of diprotic or polyprotic acids. Because the parent acid is only partially neutralized, one or more replaceable hydrogen ions remain. Typical acid salts have one or more alkali (alkaline) metal ions as well as one or more protons. Well known examples are sodium bicarbonate (NaHCO3), sodium hydrosulfide (NaHS), sodium bisulfate (NaHSO4), monosodium phosphate (NaH2PO4), and disodium phosphate (Na2HPO4). Often acid salts are used as buffers.

For example, the acid salt sodium bisulfate is the main species formed upon the half neutralization of sulfuric acid with sodium hydroxide:

H2SO4 + NaOH&nbsp;&#x2192; NaHSO4 + H2O

Acid salts compounds can act either as an acid or a base: addition of a suitably strong acid will restore protons, and addition of a suitably strong base will remove protons. The pH of a solution of an acid salt will depend on the relevant equilibrium constants and the amounts of any additional base or acid. A comparison between the Kb and Ka will indicate this: if Kb&nbsp;&gt;&nbsp;Ka, the solution will be basic, whereas if Kb&nbsp;&lt;&nbsp;'Ka, the solution will be acidic.

## Use in food

Some acid salts are used in baking. They are found in baking powders and are typically divided into low-temperature (or single-acting) and high-temperature (or double-acting) acid salts. Common low-temperature acid salts react at room temperature to produce a leavening effect. They include cream of tartar, calcium phosphate, and citrates. High-temperature acid salts produce a leavening effect during baking and are usually aluminium salts such as calciumaluminium phosphate. Some acid salts may also be found in non-dairy coffee creamers.

Salt (chemistry)

In chemistry, salts are ionic compounds that can result from the neutralization reaction of an acid and a base. They are composed of cations (positively charged ions) and anions (negative ions) so that the product is electrically neutral (without a net charge). These component ions can be inorganic such as chloride (Clâˆ’), as well as organic such as acetate (CH3COOâˆ’) and monatomic ions such as fluoride (Fâˆ’), as well as polyatomic ions such as sulfate (SO42âˆ’).

There are several varieties of salts. Salts that hydrolyze to produce hydroxide ions when dissolved in water are basic saltsand salts that hydrolyze to producehydronium ions in water are acid salts. Neutral salts are those that are neither acid nor basic salts.Zwitterions contain an anionic center and a cationic center in the same molecule but are not considered to be salts. Examples include amino acids, many metabolites, peptides and proteins.

Molten salts and solutions containing dissolved salts (e.g. sodium chloride in water) are called electrolytes, as they are able to conduct electricity. As observed in the cytoplasm of cells, in blood, urine, plant saps and mineral waters, mixtures of many different ions in solution usually do not form defined salts after evaporation of the water. Therefore, their salt content is given for the respective ions.

## Properties

### Color

Salts can appear to be clear and transparent (sodium chloride), opaque, and even metallic and lustrous (iron disulfide). In many cases the apparent opacity or transparency are only related to the difference in size of the individual monocrystals. Since light reflects from the grain boundaries (boundaries between crystallites), larger crystals tend to be transparent, while polycrystalline aggregates look like white powders. Of course, some salts are opaque.

Salts exist in many different colors, e.g.

Most minerals and inorganic pigments as well as many synthetic organic dyes are salts. The color of the specific salt is due to the presence of unpaired electrons in the d-orbital of transition elements.

### Taste

Different salts can elicit all five basic tastes, e.g., salty (sodium chloride), sweet (lead diacetate, which will cause lead poisoning if ingested), sour (potassium bitartrate), bitter (magnesium sulfate), and umami or savory (monosodium glutamate).

### Odor

Salts of strong acids

Question:what is crystillization

Answers:---Deliquescent salts have a great affinity for surrounding moisture, and readily absorb water vapours to form a solution. E.g: calcium chloride; zinc chloride, magnesium chloride; sodium hydroxide(base); lithium chloride; ammonium nitrate; magnesium nitrate; lithium sulfide; magnesium iodide; and potassium chloride ---Hydrated salts are those which contain water of crystallization - different salts attract different number of water molecules. E.g: Na2CO3+10H2O ; MgSO4+7H2O; CuSO4+5H20; CoCl2+6H2O; SnCl2+2H20; nickel(II) sulphate; aluminum nitrate ; lithium nitrate; calcium nitrate; CaCl2+6H2O; and BaCl2+2H2O. Crystallization is the the process of the removal of a solid from a solution by increasing its concentration above the saturation point, such that excess solid separates out in the form of crystals. It is used in separation and purification of a substance.

Question:The original question reads: We place a hydrated salt into a crucible whose mass is 115.624 grams. The mass of the crucible is now 117.470 grams. After heating the sample, the mass is found to be 117.188 grams. What is the formula of the hydrated ionic salt?

Answers:You can figure out the number of grams of water per grams of salt. Mass water = 117.470-117.188 = 0.282 g Mass salt (without water) = 117.188-115.624= 1.564 g. Now 0.282 g of water is 0.282/18 moles of water = 0.01567 moles. Without knowing the salt, we can not figure out how many moles there are of that. If we did we would then work out the ratio of moles of water to moles of "rest" and that would give us the formula as salt.xH2O.

Question:We had a lab where we heated Barium Chloride hydrate. In the end we are soposed to find the empirical formula for hydrated salt. Heres my data: Masses: Crucible and cover: 14.71g Crucible, cover, salt: 18.33g Crucible, cover, anhydrous salt: 17.76 If anyone could help that would be great. please explain to me how you got the answer.

Answers:Crucible and cover: 14.71g Crucible, cover, salt: 18.33g Crucible, cover, anhydrous salt:17.76g mass of water 0.57g mass of salt3.62g moles of water 0.03167 (/18) molar mass of BaCl2=208.23g/mol (anhydrous) moles of BaCl20.0174 ratio of BaCl2 : H2O ~1:2 so the formula is BaCl2.2H2O

Question:What is the difference between a hydrated salt and an anhydrous salt?

Answers:The difference is water. A hydrated salt is one that has one or more (usually more) water molecules per salt "molecule" that are actually part of the crystalline structure of the salt. Often when the hydrated salt is heated, and the water removed, (dehydrated) the crystal disintegrates to a powder of the anhydrous (literally, "without water") salt. That occurs when copper (II) sulfate pentahydrate is dehydrated by heating it. It goes from a pretty, dark blue crystal to a light blue to white powder. CuSO4*5H2O --> CuSO4 + 5H2O