Science 1.2

Why do ionic lattice networks form?

• Most ionic substances exist as solids at room temperature, decreasing distance between ions, allowing them to form a lattice.
• Larger anions alternate with smaller cations, reducing distance and increasing attraction strength.
• Ions have a sea of electrons which attract more cations, creating a lattice network.
• Ions create charges that extend in all directions, attracting multiple neighboring ions.
• Atoms can share electrons with multiple other atoms.

Which of the following substances exists as a covalent network solid?

• caffeine
• brass
• methane
• table salt
• diamond

To how many other atoms is each carbon atom in diamond joined?

• 1.0
• 2.0
• 4.0
• 3.0
• 5.0

Why can metals be bent, hammered into sheets, or pulled into wires?

• Metals exhibit translational motion, so constituent atoms can move rather freely.
• Metallic bonds have layers of atoms that can slide over each other easily.
• Metals have weak intermolecular forces, so the molecules are easier to separate.
• Metals experience a clustering effect, so they can flex without breaking.
• Metallic bonds require less energy than other intramolecular forces to change physically.

Which type of motion MOST determines a substance's state of matter?

• translational motion
• vibrational motion
• rotational motion
• oscillational motion
• transformational motion

Which change MUST take place for a solid to melt?

• broken intramolecular bonds
• increased electronegativity
• added energy
• decreased velocity
• reduced dipoles

A substance's temperature is a measure of its

• molecular acceleration
• molecular motion
• current
• potential energy
• wavelength

Which of the following substances is MOST likely to be a liquid at room temperature?

• NaCl
• SiO2
• CH4
• H2O
• CO2

If a compound has only dispersion forces,

• its electron clouds are not polarizable
• it exists in a network structure
• it never has induced dipoles
• it has no permanent dipoles
• it has a high bond energy

When a substances changes from a solid directly to a gas, it has

• recombined
• deposited
• evaporated
• condensed
• sublimated