Naming Acids and Bases

Write the formula for each of the following molecular compounds. a) carbon monoxide b) phosphorus pentachloride c) sulfur hexafluoride d) dinitrogen pentoxide e) iodine trichloride f) heptane

A. CO B. PCl 5 C. SF6 D. N2O5 E. ICl 3 F. C7H16

Write formulas for each of the following ionic compounds. a) manganese(II) carbonate b) barium iodide dihydrate c) aluminum oxide d) magnesium sulfite e) ammonium nitrate f) sodium cyanide

A. MnCO3 B. BaI2 • 2H2O C. Al2O3 D. MgSO3 E. NH4NO3 F. NaCN

Write the formula for the binary ionic compound that forms from each pair of elements. a) manganese(III) and iodine b) calcium and oxygen c) aluminum and fluorine d) potassium and sulfur e) since and bromine f) lead(IV) and oxygen

A. MnI3 B. CaO C. AlF3 D. K2S E. ZnBr2 F. PbO2

Write the name of the molecular compound represented by each formula. a) BF3 b) PBr5 c) C2H6 d) IF7 e) NO f) SiO2

A. boron trifluoride B. phosphorus pentabromide C. ethane D. iodine heptafluoride E. nitrogen monoxide F. silicon dioxide

Write the name for each of the following compounds containing polyatomic ions. a) Ca(C2H3O2)2 b) NasOH c) (NH4)2SO3 x H2O d) MgSO4 e) NaNO2 f) Ca(OH)2

A. calcium acetate B. sodium hydroxide C. ammonium sulfite monohydrate D. magnesium sulfate E. sodium nitrite F. calcium hydroxide

The metals in the following compounds can have various oxidation numbers. Predict the charge on each metal ion, and write the name for each compound. a) FeCl3 b) CuF2 c) AuBr3 d) SnBr4 e) FeS f) Pb(C2H3O2)2

A. charge: 3+; name: iron(III) chloride B. charge: 2+; name: copper(II) fluoride C. charge: 3+; name: gold(III) bromide D. charge: 4+; name: tin(IV) bromide E. charge: 2+; name: iron(II) sulfide F. charge: 2+; name: lead(II) acetate

Label the following as common names or formal names. a) alumina b) sulfuric acid c) sodium iodide d) sodium hydrogen carbonate e) dry ice f) potassium acetate

A. common B. common C. formal D. formal E. common F. formal

Which of the following substance are ionic and which are molecular? a) magnesium sulfate b) hexane c) carbon monoxide d) ozone e) cesium chloride f) colbalt(II) chloride

A. ionic B. molecular C. molecular D. molecular E. ionic F. ionic

Name the molecular compound that is represented by each of the following formulas. a) NO b) IBr c) N2O4 d) CO e) SiO2 f) CIF3

A. nitrogen monoxide B. iodine monobromide C. dinitrogen tetroxide D. carbon monoxide E. silicon dioxide F. chlorine trifluoride.

Name the ionic compound represented by each formula. a) Na2SO4 b) CaF2 c) MgBr2 x 6H2O d) Na2CO3 e) KMnO4 f) Ni(OH)2 g) NaC2H3O2

A. sodium sulfate B. calcium fluoride C. magnesium bromide hexahydrate D. sodium carbonate E. potassium permanganate F. nickel(II) hydroxide G. sodium acetate

Explain what allotropes are and give two examples.

Allotropes are different structures of molecules made up of the same element. Examples are the diamond, graphite, and fullerene allotropes of carbon; the red, white, and black allotropes of phosphorus; and the ozone and diatomic forms of oxygen.

Write formulas for a bromine atom, ion, and molecule.

Bromine atom: Br; bromide ion: Br -; bromine molecule: Br2

Explain, in terms of electron structure, why carbon usually forms four bonds.

Carbon is in Group 14 of the periodic table, and thus has four valence electrons. Each electron can be shared with another atom, forming bonds between carbon and four other atoms.

How does concrete differ from cement?

Concrete is cement to which sand and gravel have been added.

Use the structural organization of graphite to explain why it is a good lubricant.

Graphite consists of arrays of hexagons arranged in loosely held layers. These layers slide easily over one another, making graphite slippery.

What is hard water and how is it treated?

Hard water contains a high concentration of ions, especially Mg2+ and Ca2+ ions. Hard water can be treated by passing it through an ion exchange resin in which calcium and magnesium ions are each exchanged for two sodium ions.

How can you tell if a compound is ionic or molecular by examining its formula?

Ionic compounds contain both metal and nonmetal atoms, with the exception of ammonium compounds; molecular compounds contain only nonmetal atoms.

Make a table comparing the properties of ionic and molecular compounds.

Ionic: electrolyte, high melting point, hard, brittle Molecular: non-electrolyte, lowing melting point, soft or hard, nonbrittle

Predict the effect of increasing acidity of rain on the rate of formation of limestone caves.

More acidic rain will hasten the formation of caves and sinkholes in areas that contain a lot of limestone because the acids dissolve limestone as they move into the ground with the rainwater.

How is Na3HPO4 a substance with two different types of bonding?

Na2HPO4 contains two sodium metal ions bonded ionically to a monohydrogen phosphate polyatomic ion by ionic bonds. The hydrogen, phosphorus, and oxygen atoms in the polyatomic ion are held together by covalent bonds.

How can water that contains dissolved ionic compounds be separated from the ionic compounds?

One way to separate dissolved ionic compounds from water is by distillation, a process that involves heating the water until it boils, letting the water vapors escape from the ionic impurities, which have much higher boiling points, and then condensing the water back into liquid by cooling it.

Paintings discovered in a limestone cave in Lascaux, France, in 1940 were a popular tourist attraction until authorities sealed the cave to protect the paintings. Prior to the discovery of the artwork from thousands of years ago, the cave as well sealed from the atmosphere. Suggest a reason why opening the cave sped up the deterioration of the paintings.

Opening the cave allowed water vapor, oxygen, and other reactive substances in the air to move inside. These substances damaged the paintings by reacting with compounds in the cave walls and in the pigment used in the paint.

Examine the ingredient label on a tube of toothpaste. Write formulas for as many of the chemical names listed as you can. List whether each ingredient is an ionic or a covalent compound.

Students can classify these simple ingredients in toothpaste. water H2O covalent sodium fluoride NaF ionic trisodium phosphate Na3PO4 ionic titanium dioxide TiO2 ionic hydrated silica SiO2 • H2O covalent Students can find more complex ingredients in a reference book.

In Samuel Coleridge's poem The Rime of the Ancient Mariner, the mariner cried the following while on his ship far from shore. "Water, water everywhere and all the board did shrink/Water, water everywhere, nor any drop to drink." What did he mean?

The ancient mariner lamented that though he was surrounded by a sea of water, it was all salt water. Our kidneys cannot filter out all of the salt, so drinking salt water leads to dehydration and death as water is pulled from other parts of the body to dilute the salt. Water was also pulled out of the cellular structure of wood in the ship, causing the wood to shrink.

Suppose an artisan wanted to coat a clay vessel with a faint pink glaze. What material should he or she add to a transparent glaze to achieve this result?

The artisan should add to the glaze a dilute solution of chromium ions of the appropriate charge.

Explain why most elements do not occur naturally in their pure state.

The atoms of most elements have incomplete valence shells, so the atoms readily react with other atoms to complete the shells and attain stability.

Examine the formulas of the simple hydrocarbons in Table 5.8, and devise a general rule that allows you to calculate the number of hydrogen atoms present if you are given the number of carbon atoms. Use this rule to write the formula for a simple hydrocarbon containing 18 carbon atoms.

The formulas follow the pattern CnH2n + 2 . When n equals the number of carbon atoms, the number of hydrogen atoms is always 2n + 2; C18H38 .

Why don't the noble gases form compounds easily?

The noble gases each have a full valence shell of electrons, so no electrons are available for sharing or donating to another atom, and there is no room for gaining electrons from other atoms.

Write the names and symbols for an ion and element that have the same electron configuration.

The sodium ion (Na+) has the same electron configuration as neon (Ne), as does the fluoride ion (F -); the potassium ion (K+) has the same configuration as argon (Ar), as does the chloride ion (Cl -).

What information does the formula 3Ni(HCO3)2 tell you about the number of atoms of each element that are present?

There are three formula units of the compound nickel(II) hydrogen carbonate present and a total of the following atoms: 3 Ni, 6 H, 6 C, and 18 O.

How could you determine quantitatively whether the ionic compound table salt or the molecular compound table sugar is more soluble in water?

To determine whether salt or sugar is more soluble in water, the amount of each that can dissolve in equal volumes of water without precipitating out can be measured.

How would you determine quantitatively whether sodium hydroxide or calcium chloride is more deliquescent?

To determine which compound is more deliquescent, equal masses of dry samples of each compound could be weighed before and after exposure to moist air. The time required for each to liquefy could also be compared.

What happens to the composition of a hydrate when it is heated?

When a hydrate is heated, water is removed from the compound, changing the formula of the hydrate. When all the water has evaporated, an anhydrous compound remains.

A tank of a substance delivered to a factory is labeled C4H10. What is the name of the substance in the tank? What is its most likely use?

butane; fuel in disposable lighters, raw material for production of motor fuels and synthetic rubber