Simple Molecules Flashcards

All 5 cards in this deck

What is the typical size (order of magnitude) of an atom or small molecule, in standard form?

About $1 \times 10^{-10}$ m (0.1 nm).

What are the steps to draw a dot and cross diagram of a simple molecule?
e.g. hydrogen chloride, HCl

1. Write the outer electrons of each atom, using dots for one atom and crosses for the other: H has 1, Cl has 7.
2. Overlap the outer shells and put a shared pair in the overlap for each bond: 1 shared pair.
3. Draw the remaining outer electrons as pairs on each atom: Cl keeps 3 lone pairs.

In a dot and cross diagram of water, how many bonding pairs and how many lone (non-bonding) pairs are on the oxygen atom?

2 bonding pairs and 2 lone pairs.

What is a double covalent bond?

Two shared pairs of electrons (4 electrons) between two atoms.
e.g. the bond in an oxygen molecule, $\mathrm{O_2}$

True or false? In a dot and cross diagram of methane, the carbon atom is shown with 8 electrons in its outer shell.

True. Its own 4 outer electrons plus 1 from each of the 4 hydrogen atoms make 8.