Chemistry Chapter 10
What is an ionic bond?
A chemical bond that's formed when an atom transfers and electron to another Atom between metal and nonmetal.
How many bonding electrons and lone pair electrons (nonbonding electrons) are there in the Lewis structure of HCN?
8,2
What is a covalent bond?
A covalent bond is between 2 nonmetals.
When is it necessary to draw a multiple bond in an electron-dot formula?
If complete octets cannot be formed when using only single bonds between atoms, it is necessary to draw multiple bonds.
What is resonance?
Resonance occurs when we can draw two or more electron-dot formulas for the same molecule or ion.
True or False? Electrons of covalent compounds may be shared between atoms.
True
True or False? For a neutral molecule, the number of electrons in the Lewis structure is the sum of the valence electrons for the atoms.
True
Draw the correct Lewis structure for ClO4− and predict shape.
tetrahedral
Draw the correct Lewis structure for SF3+ where the positive charge is attributed to the sulfur atom. Predict shape.
trigonal pyramid
What kind of bond exists between the nitrogen atoms in the Lewis structure shown below? How many lone pairs are present on an individual nitrogen atom?
triple bond 1 lone pair
Draw the correct Lewis structure for PO43− and predict shape
tetrahedral
A covalent compound is composed of a nitrogen atom, a hydrogen atom, and a carbon atom. How many electrons should the Lewis structure of the covalent compound contain?
10
Determine the total number of valence electrons in each of the following: SBr2 NO2 CH3OH H3O+
20 e− (total valence electrons=(1 atom of S×6 valence e−)+(2 atoms of Br×7 valence e−)=20 e−) 17 e− (total valence electrons=(1 atom of N×5 valence e−)+(2 atoms of O×6 valence e−)=17 e− 14 e− (total valence electrons=(1 atom of C×4 valence e−)+(4 atoms of H×1 valence e−)+(1 atom of O×1 valence e−)=14 e−) 8 e− (total valence electrons=(1 atom of O×6 valence e−)+(3 atoms of H×1 valence e−)(−1 valence e−)=17 e−)
Enter the number of valence electrons, bonding pairs, and lone pairs (on the central atom) in each of the following Lewis structures (electron-dot formulas): H20 NH3 OBr2
A) number of valence electrons, bonding pairs, lone pairs (on central atom) =8,2,2 B)number of valence electrons, bonding pairs, lone pairs (on central atom) =8,3,1 C) number of valence electrons, bonding pairs, lone pairs (on central atom) =20,2,2
Draw the correct Lewis structure for NO2− and predict shape
Bent 120
True or False? Hydrogen atoms are often the central atom of a Lewis structure.
False
True or False? Each atom of a Lewis structure must have eight electrons.
False. Hydrogen is an exception to the octet rule because it is stable with only 2 electrons; however, there are also other exceptions to the octet rule. For example, B is stable with only 6 electrons and P and S may form expanded octets with 10 electrons.
What is a lone pair?
In chemistry, a lone pair refers to a pair of valence electrons that are not shared with another atom in a covalent bond. Lone pairs are found in the outermost electron shell of atoms
Complete each of the following statements for a molecule of H2S: A) There are ______electron groups around the central S atom. electron groups around the central SS atom. B) The electron-group geometry is ________. C) The number of atoms attached to the central SS atom is _____. D) The shape of the molecule is _______.
four tetrahedral two bent 109
In CH4 and H2O, the _____ electron groups on the central C and O atoms have a _________ arrangement. The shapes of the molecules are determined by the number of bonded atoms: CH4, with ____ bonded atoms, has a __________ shape, whereas H2O, with ____ bonded atom(s) and _____ lone pair(s) of electrons, has a _______ shape.
four, tetrahedral four, tetrahedral two, two, bent 109 (Both CH4CH4 and H2OH2O have four electron groups. Because two of those groups for H2OH2O are lone pairs, the molecular shape of H2OH2O is different than that of CH4CH4. The number of bonded atoms and lone pairs determines the molecular shape.)
