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# Chapt 10 - Chem

### Chapter 10 Chemistry

Question | Answer |
---|---|

The caloric value of food depends on the amount of energy ________ when the food is metabolized. | released. |

What VSEPR Theory? | Valence Shell electron pair repulsion theory, is based on the simple idea that electron groups, which we define as lone pairs, single bonds, multiple bonds, and even single electrons, repel one another through coulombic forces. |

What does VSEPR theory say about interior atoms? | VSEPR theory states that the repulsion between electron groups on interior atoms of a molecule determine the geometry of the molecule. |

The preferred geometry of a molecule is one in which the elctron groups have the maximum ___________. | Separation. Therefore the minimum energy possible. |

When does linear geometry occur in electron / atom formations? | Molecules that have two electron groups and no lone pairs. |

Electrons with three electron groups at 120 degree bond angles is called what? | Trigonal planar geometry. |

Different types of electron groups exert slighly different _______. | replulsions. The resulting bond angles reflect these differences. |

Tetrahedral geometry electron groups have what angle between them (usually). | 109.5 degrees. Four electron groups. |

What electron geometry is taken on by 5 electron groups"? | trigonal bipyramidal geometry. 5 electron groups. |

In trigonal bipyramidal geometry, angles between the equatorial positions (three bonds in the tirgonal plane) are ________. While the angle between the axial pos. (2 bonds on either side) is ________. | 120 degrees. 90 degrees. PCl5 is good example. |

What is the geometry for six electron groups? | Octahedral geometry. 4 of the groups lie in a single plane, 5th group above the plane, and another below it. All angles are 90 degrees. SF6 is good example. |

Electron geometry and molecular geometry are _________. | Relevant. |

Lone pair electrons generally exert slightly _________ repulsions than bonding electrons. | slightly greater. |

A lone electron pair is more _________ in space than a bonding pair, because the lone pair is attracted to only one _________, while a bonding pair is attracted to ______. | spread out, nucleus, two. |

One lone pair | |

A bent molecule that has two unpaired electrons will have an angle of... | 105 degrees. |

Angle of bent molecule with only ONE electron pair... is? | 116 - 118 degrees ( a little less than 120). |

Five electron groups with lone pairs form...? | Lone pair occupies an equatorial position. The geometry is called seesaw. Two 90 degree lone pair bonding pair repulsions. |

Hybridization of molecule with 2 electron groups. | sp - two baloons - linear |

Hybridization of molecule with 3 electron groups. | sp^2 - three baloons - trigonal planar - 120 degrees |

Hybridization of molecule with 4 electron groups. | sp^3 - four baloons - two in the x, one in the y, and one in the z. trigonal bipyramidal. - 109.5 degrees. |

Hybridization of molecule with 5 electron groups. | sp^3d - 5 baloons. - three (two on x one on z), two opposite. 90 between opposite and any on sides (x y z), 120 between side baloons. Trigonal bipyramidal |

Hybridization of molecule with 6 electron groups. | sp^3d^2 - 6 baloons - 4 on sides (x, z), and two opposite. 90 degrees between all of them. Octahedral. |

One lone pair out of 4 electron groups form what angle? (3 bonding groups) | 107 degrees. Electron geometry is tetrahedral, molecular geometry is trigonal pyramidal. |

Two lone pairs out of four electron groups. (only two bonding groups). form what angle? | 104.5 degrees. The electron geometry is tetrahedral, the geometry is bent. |

When five electron groups exist, and only two are bonding pairs, (three lone pairs), all three lone pairs occupy a _____________ position. The resulting molecular geometry is ____________. | equatorial, linear. Example is XeF2 Electron geometry is trigonal bipyramidal. |

What gets a square pyramidal molecular geometry? | Six electron groups, with one lone pair. (5 bonding, one lone). The electron geometry is octahedral. 90 degree angles between all of them. |

What gets a square planar molecular geometry? | When two of the six electron groups around the central atom are lone pairs, as in XeF4, the lone pairs occupy positions across from one another. Electron geometry is octahedral, molecular geometry is square planar. |

Give the molecular and electron geometry, and angle between bonds for the following: Electrong Groups: 2 Bonding Groups: 2 Lone pairs: 0 | E Geo: linear M Geo: Linear Approx. Bond Angle: 180 degrees. |

Larger molecules may have two ore more ___________ atoms. | interior |

If the bond in a diatomic molecule is nonpolar, the molecule as a whole will be _______. | nonpolar |

Linear geometries is polar or nonpolar? | Nonpolar |

bent geometry is polar or nonpolar? | polar |

Trigonal planar geometry is polar or nonpolar? | nonpolar |

Tetrahedral geometry is polar or nonpolar? | nonpolar |

Trigonal pyramidal is polar or nonpolar? | polar. |

What is valence bond theory? | Valence Bond Theory states: Electrons reside in quantum-mechanical orbitals localized on individual atoms. These orbitals are s,p,d,and f. |

What is equilibrium bond length? | At the distance where two atomic 1s orbitals have a significant amount of overlap, and the electrons spend time in the internuclear region. The most stable point is at the most minimum interaction, but interacting. |

Valence bond theory applied, we arrive at the following general observations: | The interaction energy is usually negative (or stabilizing) when the interacting atomic orbitals contain a total of two electrons that can spin-par (orient with opposing spins). |

Valence Bond theory tells us that a chemical bond results from what? | From the overlap of two half-filled orbitals with spin-pairing of the two valence electrons (or less commonly the overlap of a completely filled orbital with an empty orbital). |

orbitals in a molecule are _______ necessarily the same as _________. | not, the orbitals in an atom. |

What is hybridization? | Hybridization is a mathematical procedure in which the standard atomic orbitals are combined to form anew atomic orbital called hybrid orbitals that correspond more closely to the actual distribution of electrons in chem bonded atoms. |

In regards to hybrid orbitals: The greater the overlap, the _________ the bond and the ___________ the energy. | stronger, lower |

Hybridization is particularly important in carbon, which tends to form ________ bonds in its compounds and therefore always ________ | four, hybridizes. |

According to Hybridization: The number of standard atomic orbitals added together always...? | Equals the number of hybrid orbitals formed. Total # of orbitals is conserved. |

According to hybridization: The particular combinations of standard atomic orbitals added together determines the...? | the shapes and energies of the hybrid orbitals formed. |

According to hybridization: The type of hybridization that occurs is the one that yields the _____________ energy for the molecule. We use electron _____________ to predict the type of hybridization. | lowest overall, geometries |

When orbitals overlap side-by-side, the result is a __________ bond. | pi π bond |

When orbitals overlap end-to-end, the result is a ___________ | sigma bond |

A single bond is a ________ bond, a double bond consists of a ______ bond and a ________ bond, a triple bond consists of a _________ bond and two ________ bonds. | sigma, sigma and pi, sigma and two pi |