Question

Predict which of the following compounds are insoluble in water: (a) mercury(I) chloride, \(\mathrm{Hg}_{2} \mathrm{Cl}_{2}\) (b) mercury(II) chloride, \(\mathrm{HgCl}_{2}\) (c) silver bromide, \(\operatorname{AgBr}\) (d) lead(II) iodide, \(\mathrm{PbI}_{2}\)

Short answer

Mercury(I) chloride, silver bromide, and lead(II) iodide are insoluble in water.

Step-by-step solution

Understand Solubility Rules

Remember that solubility rules help determine if a compound is soluble or insoluble in water. Some key rules include: most chloride ( ext{Cl}^ ext{-}), bromide ( ext{Br}^ ext{-}), and iodide ( ext{I}^ ext{-}) salts are soluble, exceptions being those containing silver ( ext{Ag}), lead ( ext{Pb}), and mercury ( ext{Hg}).

Analyze Each Compound for Solubility

Examine each compound by applying the solubility rules: (a) Mercury(I) Chloride ( ext{Hg}_{2} ext{Cl}_{2}): Contains mercury, an exception making it insoluble. (b) Mercury(II) Chloride ( ext{HgCl}_{2}): Rule exception applies due to mercury, but still needs checking against specific rules or sources, finding it generally insoluble as special case. (c) Silver Bromide ( ext{AgBr}): Contains silver, a rule exception, making it insoluble. (d) Lead(II) Iodide ( ext{PbI}_{2}): Contains lead and iodide, leading to low solubility by rule.

Verifying Findings

Refer to tables or supplementary sources on solubility to double-check conclusions, ensuring all insights align with rules and additional specific reports for accuracy as needed, confirming conclusions.

Key concepts

Insoluble Compounds

Insoluble compounds are chemical substances that do not readily dissolve in water. One common example is when the compound contains certain metal ions like silver (Ag), lead (Pb), or mercury (Hg), as these typically form insoluble salts. For instance, when mercury(I) chloride ( Hg_{2}Cl_{2} ), silver bromide ( AgBr ), and lead(II) iodide ( PbI_{2} ) are placed in water, they do not dissolve freely and instead remain predominantly as a solid, falling out of the solution as a precipitate. Understanding these tendencies is vital for predicting compound behavior in aqueous solutions.

• Look for exceptions to common solubility rules, which help identify insoluble compounds.
• Always check if compounds contain ions associated with low solubility like Ag^+, Pb^{2+}, and Hg^{2+}.

These insights help students in analyzing chemical reactions and anticipating the formation of precipitates.

Soluble Salts

Soluble salts are ionic compounds that readily dissolve in water, leading to ions disassociating thoroughly throughout the solution. Most salts containing alkali metal ions (e.g., Li^+, Na^+, K^+) and the ammonium ion ( NH_{4}^+ ) are soluble, alongside nitrates ( NO_{3}^- ), acetates ( CH_{3}COO^- ), and most chlorides ( Cl^- ), bromides ( Br^- ), and iodides ( I^- ), unless paired with exceptions.

• These salts allow for easy mixing and reactions in aqueous solutions.
• Predicting solubility can simplify understanding chemical equilibria.

Mastering these rules is pivotal in analytical and preparative chemistry, where predicting solubility impacts procedures and desired outcomes.

Chemical Compounds Analysis

Chemical compounds analysis is an essential skill for chemists, involving classifying substances as soluble or insoluble and predicting their behavior in reactions. Such analysis demands understanding the solubility rules along with the specific structures and compositions of compounds.

• Start by identifying the component ions in each compound.
• Apply solubility rules to anticipate insoluble ones which may form precipitates.

Chemical compounds analysis extends to labs where experiments verify theoretical predictions, giving practical insights into chemical behavior. Thus, this analytical proficiency aids in experimental settings by foreseeing potential outcomes, confirming theoretical findings, and designing new experiments for innovation.