{"id":984,"date":"2022-11-18T16:00:03","date_gmt":"2022-11-18T10:30:03","guid":{"rendered":"https:\/\/www.aplustopper.com\/?p=984"},"modified":"2022-11-19T16:31:35","modified_gmt":"2022-11-19T11:01:35","slug":"classification-of-salts","status":"publish","type":"post","link":"https:\/\/www.aplustopper.com\/classification-of-salts\/","title":{"rendered":"Classification of Salts"},"content":{"rendered":"
What is a salt?<\/strong><\/p>\n A salt is formed in a neutralisation reaction<\/strong> between an acid and a base.\u00a0Salt is a general term used for the substances that are formed when an acid and a base react with each other. Example:<\/strong> Hence, a salt can be defined as follows. People also ask<\/strong><\/p>\n Table: Examples of salts from different acids<\/strong><\/p>\n Salts can be acidic, basic, or neutral. Acidic salts are formed when a strong acid reacts with a weak base. Basic salts are formed when a strong base reacts with a weak acid. When a strong acid reacts with a strong base, neutral salts are formed.<\/p>\n <\/p>\n Types of Salts:<\/strong><\/span> 1. Normal salt<\/strong><\/span> :<\/span> A salt that does not contain any replaceable hydrogen atoms or hydroxyl groups is called normal salt.<\/span> 2. Acid salt :<\/strong><\/span> When a polybasic acid is not completely neutralized by a base, the salt produced will contain replaceable hydrogen atoms. Hence, it may further take part in the reaction with the base as an acid. Such a salt is called an acid salt. For example, the salt NaHSO<\/span>4<\/sub> produced in the reaction between NaOH and H<\/span>2<\/sub>SO<\/span>4<\/sub> is an acid salt because it is capable of further reaction with the base NaOH to produce the normal salt Na<\/span>2<\/sub>SO<\/span>4<\/sub>.<\/span><\/p>\n H2<\/sub>SO4<\/sub> + NaOH \u00a0\u2192 \u00a0NaHSO<\/span>4<\/sub> + H<\/span>2<\/sub>O<\/span> Thus, an acid salt may be defined as follows. 3. Basic salt :<\/strong><\/span> When a polyacidic base reacts with lesser amount of acid than is necessary for complete neutralization, the salt produced contain hydroxyl group(s) (OH) also. Such a salt is called a basic salt.<\/span> Bi(OH)3<\/sub> + HNO3<\/sub>\u00a0 \u2192 \u00a0Bi(OH)2<\/sub>NO3<\/sub> + H2<\/sub>O<\/p>\n Salts like Pb(OH)Cl and Bi(OH)2<\/sub>NO3<\/sub> contain the OH group. These salts are called basic salts, because they can further react with the acids to form H2<\/sub>O and the corresponding normal salts.<\/p>\n Pb(OH)Cl + HCl \u00a0\u2192 \u00a0PbCl2<\/sub> +H2<\/sub>O<\/p>\n Bi(OH)2<\/sub>NO3<\/sub> + HNO3<\/sub>\u00a0 \u2192 \u00a0Bi(OH)(NO3<\/sub>)2<\/sub> + H2<\/sub>O<\/p>\n Bi(OH)(NO3<\/sub>)2<\/sub> + HNO3 \u00a0<\/sub>\u2192 \u00a0Bi(NO3<\/sub>)3<\/sub> + H2<\/sub>O<\/p>\n Thus, a basic salt is formed when a poly acidic base reacts with a lesser amount of an acid than is necessary for the formation of a normal salt.<\/p>\n 4. Double salt :<\/strong><\/span> In a double salt, there are two different negative ions and\/or positive ions. For example, the mineral dolomite, CaCO<\/span>3<\/sub>\u00b7MgCO<\/span>3<\/sub>, contains both Ca<\/span>2+<\/sup> and Mg<\/span>2+<\/sup> ions. Hence, it is a double salt. Potash alum, K<\/span>2<\/sub>SO<\/span>4<\/sub>\u00b7Al<\/span>2<\/sub>(SO<\/span>4<\/sub>)<\/span>3<\/sub>.24H<\/span>2<\/sub>O, also is a double salt.<\/span> Table: Solubility of salts in water<\/strong><\/p>\n
\nThis reaction is called a neutralization<\/strong> reaction.
\nAcid + base \u2192\u00a0salt + water
\nA salt<\/strong> is an ionic compound<\/strong> consisting of a cation<\/strong> such as a metal ion<\/strong> or an ammonium ion<\/strong> from a base and an anion from an acid<\/strong>.<\/p>\n
\nThe reaction between vinegar and baking soda is a neutralization reaction. Vinegar, as we already know, contains an acid and baking soda contains a base. When vinegar reacts with baking soda, a salt is formed. Water and carbon dioxide gas are also the products of this reaction.
\nSimilarly, common table salt is formed by the reaction of hydrochloric acid (HCl) with sodium hydroxide (NaOH).
\n
\nHCl(aq) + NaOH(aq) \u2192\u00a0NaCl(aq) + H2<\/sub>O(l)<\/p>\n
\nA salt<\/strong> is a compound formed when the hydrogen ion in an acid is replaced by a metal ion or an ammonium ion.<\/p>\n\n
\n\n
\n Acid<\/strong><\/td>\n Salt<\/strong><\/td>\n<\/tr>\n \n Hydrochloric acid<\/td>\n HCl<\/td>\n Chloride<\/strong>
\nsalts<\/td>\nSodium chloride<\/strong> Ammonium chloride<\/strong><\/td>\n NaCl
\nNH3<\/sub>Cl<\/td>\n<\/tr>\n\n Nitric acid<\/td>\n HNO3<\/sub><\/td>\n Nitrate<\/strong>
\nsalts<\/td>\nPotassium nitrate<\/strong> Aluminium nitrate<\/strong><\/td>\n KNO3<\/sub>
\nAl(NO3<\/sub>)3<\/sub><\/td>\n<\/tr>\n\n Sulphuric acid<\/td>\n H2<\/sub>SO4<\/sub><\/td>\n Sulphate<\/strong>
\nsalts<\/td>\nAmmonium sulphate<\/strong> Magnesium sulphate<\/strong><\/td>\n (NH4<\/sub>)2<\/sub>SO4<\/sub>
\nMgSO4<\/sub><\/td>\n<\/tr>\n\n Carbonic acid<\/td>\n H2<\/sub>CO3<\/sub><\/td>\n Carbonate<\/strong>
\nsalts<\/td>\nIron(ll) carbonate<\/strong> Calcium carbonate<\/strong><\/td>\n FeCO3<\/sub>
\nCaCO3<\/sub><\/td>\n<\/tr>\n\n Phosphoric acid<\/td>\n H3<\/sub>PO4<\/sub><\/td>\n Phosphate<\/strong>
\nsalts<\/td>\nIron(lll) phosphate<\/strong> Ammonium phosphate<\/strong><\/td>\n FePO4<\/sub>
\n(NH4<\/sub>)3<\/sub>PO4<\/sub><\/td>\n<\/tr>\n\n Ethanoic acid<\/td>\n CH3<\/sub>COOH<\/td>\n Ethanoate<\/strong>
\nsalts<\/td>\nLead(ll) ethanoate<\/strong> Copper(ll) ethanoate<\/strong><\/td>\n Pb(CH3<\/sub>COO)2<\/sub>
\nCu(CH3<\/sub>COO)2<\/sub><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\nThe different types of salts are: normal salt, acid salt, basic salt and double salt.<\/p>\n
\nExamples :<\/strong>
\nNa2<\/sub>SO4<\/sub> obtained in the reaction between H2<\/sub>SO4<\/sub> and NaOH is a normal salt because it is formed by the complete replacement of both the H atoms of H2<\/sub>SO4<\/sub>,
\nSimilarly, calcium su1phate (CaSO4<\/sub>), sodium phosphate (Na3<\/sub>PO4<\/sub>) and potassium phosphate (K3<\/sub>PO4<\/sub>) are also normal salts.<\/p>\n
\nNaHSO4<\/sub> + NaOH \u00a0\u2192 \u00a0Na<\/span>2<\/sub>SO<\/span>4<\/sub> + H<\/span>2<\/sub>O<\/span><\/p>\n
\nA salt that contains replaceable hydrogen atoms is called an acid salt.
\nExamples :<\/strong>
\nNaHSO4<\/sub>, NaH2<\/sub>PO4<\/sub> and Na2<\/sub>HPO4<\/sub> are examples of acid salts.<\/p>\n
\nExamples :<\/strong>
\n1 mole of Pb(OH)2<\/sub> requires 2 moles of HCl for complete neutralization. But when 1 mole of Pb(OH)2<\/sub> is made to react with 1 mole of HCl, some Pb(OH)2<\/sub> is left unreacted. The salt produced is not PbCl2<\/sub>, but Pb(OH)Cl.
\n
\nSimilarly, when one mole of Bi(OH)3<\/sub> is reacted with 1 mole of HNO3<\/sub>, the salt Bi(OH)2<\/sub>NO3<\/sub> is formed.<\/p>\n
\nDouble salts exist only in the solid state. When dissolved in water, they break up into a mixture of two separate salts. For example, when potash alum is dissolved in water, it breaks up as follows.
\n<\/p>\nSolubility of salts in water<\/strong><\/h3>\n
\n
\n\n
\n Type of salt<\/strong><\/td>\n