Representative Metals, Metalloids, and Nonmetals

Why does the reactivity of the alkali metals decrease from cesium to lithium?

Predict the formulas for the nine compounds that may form when each species in column\({\bf{1}}\) of Table \({\bf{18}}.{\bf{3}}\)reacts with each species in column 2.

Sodium chloride and strontium chloride are both white solids. How could you distinguish one from the other?

The reaction of quicklime,\({\rm{CaO}}\), with water produces slaked lime, \({\rm{Ca}}{({\rm{OH}})_2}\), which is widely used in the construction industry to make mortar and plaster. The reaction of quicklime and water is highly exothermic: \({\rm{CaO}}(s) + {{\rm{H}}_2}{\rm{O}}(l) \to {\rm{Ca}}{({\rm{OH}})_2}(s)\;\;\;\Delta H =   - 350\;{\rm{kJ}}\;{\rm{mo}}{{\rm{l}}^{ - 1}}\)

(a) What is the enthalpy of reaction per gram of quicklime that reacts?

(b) How much heat, in kilojoules, is associated with the production of 1 ton of slaked lime?

How many moles of ionic species are present in \({\bf{1}}.{\bf{0}}{\rm{ }}{\bf{L}}\) of a solution marked \({\bf{1}}.{\bf{0}}M\) mercury (I) nitrate?

What is the mass of fish, in kilograms, that one would have to consume to obtain a fatal dose of mercury, if the fish contains \({\bf{30}}\)parts per million of mercury by weight? (Assume that all the mercury from the fish ends up as Mercury (II) chloride in the body and that a fatal dose is \({\bf{0}}.{\bf{20}}{\rm{ }}{\bf{g}}\) of\({\bf{HgC}}{{\bf{l}}_2}\).) How many pounds of fish is this?

Does metallic tin react with\({\bf{HCl}}\)?

What is tin pest, also known as tin disease?

Compare the nature of the bonds in \({\bf{PbC}}{{\bf{l}}_2}\)to that of the bonds in \({\bf{PbC}}{{\bf{l}}_4}\).

Is the reaction of rubidium with water more or less vigorous than that of sodium? How does the rate of reaction of magnesium compare?

Write an equation for the reduction of cesium chloride by elemental calcium at high temperature.

Why is it necessary to keep the chlorine and sodium, resulting from the electrolysis of sodium chloride, separate during the production of sodium metal?

Give balanced equations for the overall reaction in the electrolysis of molten lithium chloride and for the reactions occurring at the electrodes. You may wish to review the chapter on electrochemistry for relevant examples.

What mass, in grams, of hydrogen gas forms during the complete reaction of \({\bf{10}}.{\bf{01}}{\rm{ }}{\bf{g}}\) calcium with water?

How many grams of oxygen gas are necessary to react completely with \({\bf{3}}{\bf{.01 \times 1}}{{\bf{0}}^{{\bf{21}}}}\) atoms of magnesium to yield magnesium oxide?

Magnesium is an active metal; it burns in the form of powder, ribbons, and filaments to provide flashes of brilliant light. Why is it possible to use magnesium in construction?

Why is it possible for an active metal like aluminium to be useful as a structural metal?

Describe the production of metallic aluminum by electrolytic reduction.

What is the common ore of tin and how is tin separated from it?

A chemist dissolves a \({\bf{1}}.{\bf{497}} - {\bf{g}}\) sample of a type of metal (an alloy of \({\bf{Sn}},{\rm{ }}{\bf{Pb}},{\rm{ }}{\bf{Sb}},\)and\({\bf{Cu}}\)) in nitric acid, and metastannic acid,\({{\bf{H}}_2}{\bf{Sn}}{{\bf{O}}_3}\), is precipitated. She heats the precipitate to drive off the water, which leaves \({\bf{0}}.{\bf{4909}}\)g of tin (IV) oxide. What was the percentage of tin in the original sample?

Consider the production of \({\bf{100}}\) kg of sodium metal using a current of \({\bf{50}},{\bf{000}}{\rm{ }}{\bf{A}},\) assuming a \({\bf{100}}\% \) yield.

(a) How long will it take to produce the 100 kg of sodium metal?

(b) What volume of chlorine at \({\bf{25}}{\rm{ }}^\circ {\bf{C}}\)and \({\bf{1}}.{\bf{00}}\) atm forms?

What mass of magnesium forms when \({\bf{100}},{\bf{000}}{\rm{ }}{\bf{A}}\) is passed through a \({\bf{MgC}}{{\bf{l}}_2}\)melt for \({\bf{1}}.{\bf{00}}{\rm{ }}{\bf{h}}\) if the yield of magnesium is \({\bf{85}}\% \) of the theoretical yield?

Give the hybridization of the metalloid and the molecular geometry for each of the following compounds or ions. You may wish to review the chapters on chemical bonding and advanced covalent bonding for relevant examples.

\((a){\rm{Ge}}{{\rm{H}}_4}\)

\((b){\rm{Sb}}{{\rm{F}}_3}\)

\((c){\rm{Te}}{({\rm{OH}})_6}\)

\((d){{\rm{H}}_2}{\rm{Te}}\)

\((e){\rm{Ge}}{{\rm{F}}_2}\)

\((f){\rm{TeC}}{{\rm{l}}_4}\)

\((g){\rm{SiF}}_6^{2 - }\)

\((h){\rm{SbC}}{{\rm{l}}_5}\)

\((i){\rm{Te}}{{\rm{F}}_6}\)

Write a Lewis structure for each of the following molecules or ions. You may wish to review the chapter on chemical bonding.

\((a)\;{{\rm{H}}_3}{\rm{BP}}{{\rm{H}}_3}\)

\((b)\;{\rm{BF}}_4^ - \)

\((c)\;{\rm{BB}}{{\rm{r}}_3}\)

\((d)\;{\rm{B}}{\left( {{\rm{C}}{{\rm{H}}_3}} \right)_3}\)

\((e)\;{\rm{B}}{({\rm{OH}})_3}\)

Using only the periodic table, write the complete electron configuration for silicon, including any empty orbitals ins the valence shell. You may wish to review the chapter on electronic structure.

Describe the hybridization and the bonding of a silicon atom in elemental silicon.

Silicon reacts with sulfur at elevated temperatures. If \({\bf{0}}.{\bf{0923}}{\rm{ }}{\bf{g}}\) of silicon reacts with sulfur to give \({\bf{0}}.{\bf{3030}}{\rm{ }}{\bf{g}}\) of silicon sulfide, determine the empirical formula of silicon sulfide.

Name each of the following compounds:

\((a){\rm{Te}}{{\rm{O}}_2}\)

\((b){\rm{S}}{{\rm{b}}_2}\;{{\rm{S}}_3}\)

\((c){\rm{Ge}}{{\rm{F}}_4}\)

\((d){\rm{Si}}{{\rm{H}}_4}\)

\((e){\rm{Ge}}{{\rm{H}}_4}\)

Why is boron limited to a maximum coordination number of four in its compounds?

Write a formula for each of the following compounds:

(a) Silicon dioxide

(b) Silicon tetra iodide

(c) Silane

(d) Silicon carbide

(e) Magnesium silicide

A hydride of silicon prepared by the reaction of \({\rm{M}}{{\rm{g}}_2}{\rm{Si}}\) with acid exerted a pressure of 306 torr at \({26^\circ }{\rm{C}}v\)in a bulb with a volume of\(57.0\;{\rm{mL}}\). If the mass of the hydride was\(0.0861\;{\rm{g}}\), what is its molecular mass? What is the molecular formula for the hydride?

Suppose you discovered a diamond completely encased in a silicate rock. How would you chemically free the diamond without harming it?

Carbon forms a number of allotropes, two of which are graphite and diamond. Silicon has a diamond structure. Why is there no allotrope of silicon with a graphite structure?

Nitrogen in the atmosphere exists as very stable diatomic molecules. Why does phosphorus form less stable \({{\bf{P}}_4}\)molecules instead of \({{\bf{P}}_2}\)molecules?

Determine the oxidation number of each element in each of the following compounds: 

(a) \({\bf{HCN}}\)

(b) \(O{F_2}\)

(c) \(AsC{l_3}\)

Determine the oxidation state of sulfur in each of the following: 

(a) \(S{O_3}\)

(b) \(S{O_2}\)

(c) \(SO_3^{2 - }\)

Arrange the following in order of increasing electronegativity: \({\bf{F}};{\rm{ }}{\bf{Cl}};{\rm{ }}{\bf{O}};\)and S.

Why does white phosphorus consist of tetrahedral \({P_4}\)molecules while nitrogen consists of diatomic \({N_2}\) molecules?

Why does hydrogen not exhibit an oxidation state of -1 when bonded to nonmetals?

The reaction of calcium hydride,\({\rm{Ca}}{{\rm{H}}_{\rm{2}}}\), with water can be characterized as a Lewis acid-base reaction: \({\rm{Ca}}{{\rm{H}}_{\rm{2}}}\left( {\rm{s}} \right){\rm{  +  2}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right) \to {\rm{Ca}}{\left( {{\rm{OH}}} \right)_{\rm{2}}}\left( {{\rm{aq}}} \right){\rm{  +  2}}{{\rm{H}}_{\rm{2}}}\left( {\rm{g}} \right)\).

Identify the Lewis acid and the Lewis base among the reactants. The reaction is also an oxidation-reduction reaction. Identify the oxidizing agent, the reducing agent, and the changes in oxidation number that occur in the reaction.

In drawing Lewis structures, we learn that a hydrogen atom forms only one bond in a covalent compound. Why?

What mass of \(Ca{H_2}\) is necessary to react with water to provide enough hydrogen gas to fill a balloon at 20 °C and 0.8 atm pressure with a volume of 4.5 L? The balanced equation is: 

\(Ca{H_2}\left( s \right) + 2{H_2}O\left( l \right) \to Ca{\left( {OH} \right)_2}\left( {aq} \right) + 2{H_2}\left( g \right)\)

What mass of hydrogen gas results from the reaction of 8.5 g of \(KH\) with water?

\(KH{\rm{ }} + {\rm{ }}{H_2}O \to KOH{\rm{ }} + {\rm{ }}{H_2}\)

Carbon forms the \({\rm{CO}}_{\rm{3}}^{{\rm{2 - }}}\)ion, yet silicon does not form an analogous \({\rm{SiO}}_{\rm{3}}^{{\rm{2 - }}}\)ion. Why?

Complete and balance the following chemical equations:

(a) Hardening of plaster containing slaked lime

\(Ca{\left( {OH} \right)_2} + C{O_2} \to \)

(b) Removal of sulfur dioxide from the flue gas of power plants

\(CaO{\rm{ }} + {\rm{ }}S{O_2} \to \)

(c)The reaction of baking powder that produces carbon dioxide gas and causes bread to rise

\(NaHC{O_3} + Na{H_2}P{O_4} \to \)

Heating a sample of \(N{a_2}C{O_3} \cdot x{H_2}O{\rm{ }}\) weighing 4.640 g until the removal of the water of hydration leaves 1.720 g of anhydrous\(N{a_2}C{O_3}\). What is the formula of the hydrated compound?

How many tons of \(C{a_3}{\left( {P{O_4}} \right)_2}\)are necessary to prepare 5.0 tons of phosphorus if the yield is 90 % ?

For each of the following, indicate the hybridization of the nitrogen atom (for\({{\bf{N}}_{\bf{3}}}\),the central nitrogen).

(a)\({{\bf{N}}_{\bf{2}}}{{\bf{F}}_{\bf{4}}}\)

(b)\(\;{\bf{N}}{{\bf{H}}_{\bf{2}}}^ - \)

(c) \({\bf{N}}{{\bf{F}}_{\bf{3}}}\)

(d) \({{\bf{N}}_{\bf{3}}} - \)

How many grams of gaseous ammonia will the reaction of 3.0 g hydrogen gas and 3.0 g of nitrogen gas produce?

Although \(P{F_5}\) and \(AS{F_5}\) are stable, nitrogen does not form \(N{F_5}\)molecules. Explain this difference among members of the same group.