molecular geometry

Angle between 2 bonds is called the…

bond angle

bond angle for a linear molecule is…

180^o

when we predict the shape of a molecule we assume that the bonding pairs…

repel as far as possible

trigonal planar bond angle?

120^o

if a molecule has 3 electron pairs, we say that its shape is…

trigonal planar

if a molecule has 4 bonding pairs and 0 lone pairs its shape is…

tetrahedral

tetrahedral bond angle…

109.5^o

as the number of lone pairs in a molecule increase the…

bond angle decreases

an electron pair exists in a——— cloud

charge

lone pairs repel more than bonding pairs so if theres a lone pair the distance between two bonding pairs…

decreases

a lone pair has…

a bigger charge cloud than a bonding pair therefore repels more than bonding pairs

we would expect the repusion between a lone pair and a bonding pair to be…

1) less than the repulsion between 2 lone pairs

2)more than the repulsion between 2 bonding pairs

The order of the electron pair repulsion is:

lone pair-lone pair >lone pair-bonding pair> bonding pair-bonding pair

why is the bond angle smaller in ammonia than in methane?

CH₄ has 4 bonding pairs of electrons

NH₃ has 3 bonding pairs and 1 lone pair

lone pairs take up more space and repel more strongly than bonding pairs

so bonding pairs in NH₃ are pushed closer together and bond angle is closer together

If a molecule has 2 bonding pairs and 1 lone pair its shape is…

bent

bond angle for bent shape is…

118^o

if a molecule has 3 bonding pairs and 1 lone pair we say that its shape is…

trigonal pyrimidal

bond angle of trigonal pyrimidal shape…

107^o

If a molecule has 5 electron pairs and 0 lone pairs, we say that its shape is…

trigonal bipyrimidal

The bond angles for a trigonal bipyramidal molecule are...

a)120^o

b)90^o

The shape the electron pairs form is…

• trigonal bipyramidal

If a molecule has 4 bonding pairs and 1 lone pair, we say that its shape is...

sawhorse.

seesaw.

trigonal bipyramidal.

the bond angles for a seesaw are..

102^o

87^o

If a molecule has 3 bonding pairs and 2 lone pairs, we say that its shape is...

And the bond angles are...

T-shaped

84^o and 90^o

If a molecule has 2 bonding pairs and 3 lone pairs, we say that its shape is...

And the bond angle is...

linear

180°

Name this molecular shape and state the sizes of its bond angles.

Name:

seesaw

Angle X:

102°

Angle Y:

87°

ICl₃ has 3 bonding pairs and 2 lone pairs. Which of the following statements is true?

The arrangement of the electron pairs is trigonal bipyramidal but the atoms are t-shaped

Which of the following electron pair combinations give molecules a linear shape??

2 bonding pairs and 0 lone pairs

2 bonding pairs and 3 lone pairs

explain why the fluorine atoms in XeF2​ occupy a linear geometry.

electron pairs occupy a trigonal bipyramidal arrangement.

There are 2 bonding pairs and 3 lone pairs.

Lone pairs of electrons take up more space and repel more strongly than bonding pairs.

If fluorine atoms occupy the positions above and below the plane, it ensures that lone pairs are maximally separated from one another (120°).

What are the bond angles in this molecule??

90^o

What are the bond angles in this molecule??

90^o

If a molecule has 6 electron pairs, we say that its shape is...

And the bond angles are...

octahedral.

90°

If a molecule has 4 bonding pairs and 2 lone pairs, we say that its shape is...

And the bond angles are...

square planar.

90°

Which of the following molecular shapes contain 90° bond angles??

Trigonal bipyramidal

Square planar

Octahedral

bond angle of 2 lone pairs and 2 bonding pairs…

104.5^o

planar

In planar molecules, all atoms lie in a single plane

Explain why AsH₃ has a trigonal pyramidal shape.

There are 4 electron pairs around the arsenic atom.

The 4 electron pairs repel each other to form a tetrahedral arrangement, where they are maximally separated from one another.

Of the 4 electron pairs, 3 are bonding pairs and 1 is a lone pair.

Lone pairs repel more strongly than bonding pairs.

So, the molecule has a trigonal pyramidal shape with a 107° bond angle.

What is the bond angle in CO2​??

180^o

When we predict the shape of a molecule with a double bond, we assume that...(2)

electron pairs in a double bond don’t repel each other

the double bond repels a similar amount to a single bond

When two atoms share a single pair of electrons, the electrons exist in a(n)...

sigma bond

When two atoms share a second pair of electrons, the electrons exist in a(n)...

pi bond

Using the dot and cross diagram, predict the shape of HCN.

shape:linear

bond angle:180^o

By drawing a dot and cross diagram, state the number of electron pairs around the central atom in ClF₂+…

Both fluorine and chlorine have 7 electrons in their valence shell.

The ion has a positive charge, so we remove an electron from the least electronegative atom (chlorine).