Shapes of Molecules - exam practice
Shapes of Molecules
Question 1 of 4
Draw a diagram to show the shape of a molecule of ammonia. Include any lone pairs of electrons and give the value of the bond angle.
What is the name of the shape of the ammonia molecule, NH3?
Ammonia, NH3, can react with a hydrogen ion, H+, to form an ammonium ion, NH4+, which contains a dative covalent bond.
Explain how the dative covalent bond in NH4+ is formed.
State the new shape and bond angle of the ammonium ion.
State the meaning of the term electronegativity.
The table below shows the Pauling electronegativity values of some Period 3 elements.
Deduce the type of bonding in sulfur hexachloride, SCl6.
Explain your reasoning, using the table of electronegativity values above.
Draw the shape of a molecule of SF6. Include a value of the F-S-F bond angle.
Explain why SF6 has the shape you have drawn.
Ammonia reacts with aluminium chloride as shown by the equation:
NH3 + AlCl3 ➔ H3NAlCl3
Draw a diagram to illustrate the shape of a molecule of AlCl3.
Give the value of the bond angle.
Name the type of bond formed between N and Al in H3NAlCl3.
Explain how the value of the Cl-Al-Cl bond angle in AlCl3 changes, if at all, on formation of the compound H3NAlCl3.
This question is about the group 3 element boron.
Boron trifluoride can react with a fluoride ion as shown by the equation;
BF3 + F- ➔ BF4-
Draw a diagram to show the shape of the BF3 molecule.
State its shape.
Explain why the BF3 molecule has the shape that you have drawn in part a).
Draw a diagram to show the shape of the BF4- ion.
State its shape.
Name the type of bond formed in the reaction between BF3 and F- to form BF4-.
Explain how this bond is formed in terms of electrons involved.