Answer the following questions about the solubility of Ca(OH)2 (K sp = 1.3 × 10 −6).
Write a balanced chemical equation for the dissolution of Ca(OH)2(s) in pure water.
Calculate the molar solubility of Ca(OH)2 in 0.10 M Ca(NO3)2 .
In the box below, complete a particle representation diagram that includes four water molecules with proper orientation around the Ca2+ ion.
Represent water molecules as
Did this page help you?
Answer the following questions about Mg(OH)2. At 25°C, the value of the solubility product constant, Ksp for Mg(OH)2(s) is 1.8 x 10−11 .
Calculate the number of grams of Mg(OH)2 (molar mass 58.32 g/mol) that is dissolved in 100. mL of a saturated solution of Mg(OH)2 at 25°C.
The energy required to separate the ions in the Mg(OH)2 crystal lattice into individual Mg2+(g) and OH−(g) ions, as represented in the table below, is known as the lattice energy of Mg(OH)2(s) . As shown in the table, the lattice energy of Sr(OH)2(s) is less than the lattice energy of Mg(OH)2(s) . Explain why in terms of periodic properties and Coulomb's law.
|
Reaction |
Lattice Energy (kJ/mol) |
|
Mg(OH)2(s) → Mg2+(g) + 2 OH−(g) |
2900 |
|
Sr(OH)2(s) → Sr2+(g) + 2 OH−(g) |
2300 |
Did this page help you?
A Lewis electron-dot diagram of the oxalate ion, C2O42−, is shown.
Identify the hybridization of the valence orbitals of either carbon atom in the oxalate ion.
Silver oxalate, Ag2C2O4 (s), is slightly soluble in water. The value of Ksp for Ag2C2O4 is 5.40 × 10−12.
Did this page help you?
A student is studying the properties of CaSO4 and PbSO4 . The student has samples of both compounds, which are white powders.
The student tests the electrical conductivity of each solid and observes that neither solid conducts electricity. Describe the structures of the solids that account for their inability to conduct electricity.
The student places excess CaSO4(s) in a beaker containing 100 mL of water and places excess PbSO4(s) in another beaker containing 100 mL of water. The student stirs the contents of the beakers and then measures the electrical conductivity of the solution in each beaker. The student observes that the conductivity of the solution in the beaker containing the CaSO4(s) is higher than the conductivity of the solution in the beaker containing the PbSO4(s).
Which compound is more soluble in water, CaSO4(s) or PbSO4(s) ? Justify your answer based on the results of the conductivity test.
The left side of the diagram below shows a particulate representation of the contents of the beaker containing the CaSO4(s) from the solution conductivity experiment.
Draw a particulate representation of PbSO4(s) and the ions dissolved in the solution in the beaker on the right in the diagram. Draw the particles to look like those shown to the right of the beaker. Draw an appropriate number of dissolved ions relative to the number of dissolved ions in the beaker on the left.
The student attempts to increase the solubility of CaSO4(s) by adding 10.0 mL of 2 M H2SO4(aq) to the beaker, and observes that additional precipitate forms in the beaker. Explain this observation.
Did this page help you?