Solid Sodium Iodide Is Slowly Added to a Solution That

question 21

Multiple Choice

Solid sodium iodide is slowly added to a solution that is 0.0050 M Pb²⁺ and 0.0050 M Ag⁺. [K_sp (PbI₂) = 1.4 *10^-8; K_sp (AgI) = 8.3 *10^-17] Calculate the Ag⁺ concentration when PbI₂ just begins to precipitate.

• A) 3.0 * 10^-14 M
• B) 5.0 * 10^-14 M
• C) 7.0 * 10^-14 M
• D) 9.0 * 10^-14 M
• E) None of the above

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Definitions:

Allowance for Doubtful Accounts

A contra asset account that represents the estimated proportion of accounts receivable that may not be collectable.

Direct Write-off Method

An accounting approach where uncollectible accounts receivable are directly written off against income at the time they are deemed unrecoverable.

Uncollectible Accounts Receivable

Debts owed to a company that are considered to be uncollectible from the debtor, often leading to the account being written off as a bad debt expense.

Allowance for Doubtful Accounts

An estimate of the amount of accounts receivable that may not be collectible, serving as a contra account to adjust the value of total receivables.