l0Z: Chapter 3 Chemical Bonds
3.44 Write the formula for the ionic compound formed from the following pairs of ions: (a) Iron(II) ion and chloride ion (b) Calcium ion and hydroxide ion (c) Ammonium ion and phosphate ion (d) fin(Il) ion and fluoride ion
3.45 Which formulas are not correct? For each that is not cor:rect, write the correct formula. (a) Ammonium phosphate; (NH)2POa (b) Barium carbonate; Ba2CO3 (c) Aluminum sulfide; A12S3 (d) Magnesium sulfrde; MgS
3.46 Which formulas are not correct? For each that is not correct, write the correct formula. (a) Calcium oxide; CaO2 (b) Lithium oxide;LiO (c) Sodium hydrogen phosphate; NaHPOa (d) Ammonium nitrate; NH4NOS
Section 3.6 How Do We Name lonic Compounds? 3.47 Answer true or false.
(a) The name of a binary ionic compound consists of the name of the positive ion followed by the name of the negative ion.
(b) In naming binary ionic compounds, it is necessary to state the number of each ion present in the compound.
(c) The formula of aluminum oxide is Al2O3. (d) Both copper(Il) oxide and cupric oxide are
acceptable names for CuO. (e) The systematic name for Fe2O3 is iron(Il) oxide. (f) The systematic name for FeCO3 is iron carbonate. (g) The systematic name for NaH2POa is sodium di-
hydrogen phosphate. (h) The systematic name for I$HPO4 is dipotassium
hydrogen phosphate. (i) The systematic name for Na2O is sodium oxide. (j) fne systematic name for PCl3 is potassium
chloride. (k) The formula of ammonium carbonate is NHaCO3.
3.4!t Potassium chloride and potassium bicarbonate are = used as potassium dietary supplements. Write the
formula of each compound. 3.49 Potassium nitrite has been used as a vasodilator and
as an antidote for cyanide poisoning. Write the for- mula of this compound.
3.50 Name the polyatomic ion(s) in each compound. (a) Na2SO, (b) KNO3 (c) CszCOs (d) NH4OH (e) I(zHPOa
3.51 Write the formulas for the ions present in each compound. (a) NaBr (b) FeSO, (c) Mgs(POJz (d) KH2PO4 (e) NaHCO, (fl Ba(NOr),
3.d;2 Name these ionictompounds:-- (a) NaF ft) MgS (d) BaCl, (g) Srs(Porz
(c) Al2O3 (e) Ca(HSOs)z (f) KI (h) Fe(OH)z (i) NaHzPOa
0) Pb(CHaCOO), (k) BaHz G)(NHr,HPO4 3.53 Write formulas for the following ionic compounds:
(a) Potassium bromide (b) Calcium oxide (s) Mercury(Il) oxide (d) Copper(Il) phosphate (e) Lithium sulfate (0 Iron(III) sulfrde
3.54 Write formulas for the following ionic compounds: (a) Ammonium hydrogen sulfite (b) Magnesium acetate (c) Strontium dihydrogen phosphate (d) Silver carbonate (e) Strontium chloride (f) Barium permanganate
Section 3.7 What ls a Covalent Bond? 3.55 Answer true or false.
(a) A covalent bond is formed behareen hnro atoms whose difference in electronegativity is less than 1.9.
(b) If the difference in electronegativity between two atoms is zero (they have identical electronega- tivities), then the two atoms will not form a cova- lent bond.
(c) A covalent bond formeil by sharing two electrons is called a double bond.
(d) In the hydrogen molecule (Hz), the shared pair of electrons completes the valence shell of each hydrogen.
(e) In the molecule CHa, each hydrogen has an elec- tron configuration like that ofhelium and carbon has an electron configuration like that ofneon.
(f) In a polar covalent bond, the more electronega- tive atom has a partial negative charge (6-) and the less electronegative atom has a partial posi- tive charge (6+).
(g) These bonds are arranged in order ofincreasing polarity C-H < N-H < O-H.
(h) These bonds are arranged in order ofincreasing polarity H-F < H-Cl < H-Br.
(i) A polar bond has a dipole with the negative end located at the more electronegative atom.
0) In a single bond, two atoms share one pair of electrons; in a double bond, they share two pairs ofelectrons; and in a triple bond, they share three pairs of electrons.
(k) The Lewis structure for ethane, C2H6, must shod! eight valence electrons.
0) The Lewis structure for formaldehyde, CH2O, must show 12 valence electrons.
(m) The Lewis structure for the ammonium ion, NHa+, must show nine valence electrons.
(n) Atoms of third-period elements can hold more than eight electrons in their valence shells.