Classifying Electrolytes

Electrolytes are substances which, when liquified in water, break up intocations (plus-charged ions) and anions (minus-charged ions). We say they ionize.

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Strong electrolytes ionize completely (100%), while weak electrolytesionize only partially (generally on the order of 1–10%). That is, the primary speciesin solution for strong electrolytes are ions, while the primary specie in solution for weak electrolytes is the un-ionized compound itself.Strong electrolytes fall into 3 categories: strong acids,solid bases, and salts. (Salts are periodically also called ionic compounds, yet really strongbases are ionic compounds too.) The weak electrolytes incorporate weak acids and also weak bases.Examples of strong and also weak electrolytes are provided below:
Strong Electrolytes solid acidsHCl, HBr, HI, HNO3, HClO3, HClO4, and H2SO4 strong basesNaOH, KOH, LiOH, Ba(OH)2, and Ca(OH)2 saltsNaCl, KBr, MgCl2, and many kind of, many moreWeak Electrolytes weak acidsHF, HC2H3O2 (acetic acid), H2CO3 (carbonic acid), H3PO4 (phosphoric acid), and also many more weak basesNH3 (ammonia), C5H5N (pyridine), and also several more, all containing "N"

Being Able to Classify Electrolytes Is Critical

As chemists, we need to have the ability to look at a formula such as HCl or NaOH and also quickly knowwhich of these classifications it is in, bereason we must be able torecognize what we are functioning via (ions or compounds) as soon as we are working withchemicals. We should understand, for example, that a bottle labeled "NaCN" (a salt) really containsno NaCN, fairly Na+ and also CN–, or that a bottle labeled "HCN" (a weak acid) is principally HCNthrough a small amount of H+ and also CN– likewise existing. The difference in between simply opening a bottle labeled "HCN" and also one labeled "NaCN" might be your life, as HCN, or hydrogen cyanide, is a toxic gas, while CN–, or cyanide ion, being an ion, isn"t a gas and is just transfered in solid or solution create. Nonetheless, it is cyanide ion, CN–, that is the killer. (It locks onto the Fe3+ in hemoglobin, resulting in much less oxygen to acquire to your brain.) Cyanide is current in both bottles, and if it is transfered to your bloodstream either as CN– or as HCN, it will kill you.

Six Steps for Categorizing Electrolytes

So exactly how perform we categorize compounds based on their formula? One handy technique is outlined below:
Tip 1Is it one of the seven strong acids?Step 2Is it of the form Metal(OH)n? Then it"s a solid base.Step 3Is it of the form Metal(X)n? Then it"s a salt.Tip 4Does it"s formula begin via "H"? It"s probably a weak acid.Tip 5Does it have actually a nitrogen atom? It may be a weak base.

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Tip 6None of those? Call it a nonelectrolyte.
Note that tbelow are ambiguities here founding in Step 4. That"s simply the means it is. To recognize whether a substance is a weak acid or weak base you have to understand more than the molecular formula, specifically for compounds containing carbon. (A structural formula, which shows the detailed connections of atoms is often necessary.)SummaryIn summary, understand the more widespread facet names and symbols, memorize the seven solid acids, have the ability to spot a steel (know at least wright here they are on theroutine table), memorize at leastern a few of the even more widespread weak acids and weak base,and you will certainly be in excellent form. YOU CAN DO IT!