Illinois Resource: Salts

Fill in the blank

Salts are ___ compounds that when dissolved in water, break up completely into ___ with a positive charge and ____ with a negative charge

ionic \text{cations} \text{anions}

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The identify of the ions created when a salt dissolves determines whether the final solution is acidic, basic, or neutral,

how can we determine if a salt solution dissolved in waster will be acidic, neutral, or basic

ask yourself what cations/ anions are formed in solution?

Dlo either of these ions react with water?

if an ion reacts with water, what products are formed?

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An ion must react with water to influence pH by forming either acidic or basic products.

Do cations on groups 1 & 2 interact with water??

No, they do not interact significantly with water. They are typically found as counter ions with strong bases

what counterions are frequently found as with strong acids?

Anions like chloride, bromide, and sulfate are commonly found as counterions with strong acids.

what is the charge of SO4?

The sulfate ion, $SO_4^{2-}$, carries a charge of negative two.

what is the charge of ClO4?

The perchlorate ion, $ClO\text{ }_4^{-}$, carries a charge of negative one.

what is the charge of NO3?

The nitrate ion, $NO\text{ }\text{ }_3^{-}$, carries a charge of negative one.

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Groups 1 & 2 of the periodic table and 7 do not interact with water. since they do not interact with water they cannot affect pH

What is the pH of a solution containing 0.5M NaCl?

The pH of a solution containing 0.5M NaCl is approximately 7, as NaCl is a neutral salt that does not affect the acidity or basicity of the solution.

It can be difficult to disassociate ions

Here are some helpful hints:

Cations are always written to the left anions are written to the right

cations are usually alkali or earth metals, or nitrogen containing

Anions are nonmetals or polyatomic ions

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the cation of an acidic salt is usually the conjugate acid of a weak baseor a strong acid, while the anion is typically derived from a strong acid. This composition results in a solution that is acidic.

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with basic salts dissolved the cation is usually an alkali or earth metal of the initial no dissociated salt. Anion are conjugate bases of a weak acid of the initially non dissociated salt. The anion of the non dissociated salt is usually the conjugate of a weak base (once you dissociate it into water and break it down)

true or false

larger Ka values indicate stronger acids and lower exponents

True