A person uses a match to light charcoal in a grill. Which statement describes a chemical property of the charcoal?

• It has a high boiling point.

• It is an electrical insulator.

• It is flammable.

• It has a high temperature.

Which statement describes a physical property related to the particles that make up a material?

• A fruit has a sour taste because some of the compounds that make it up are acids.

• Salt crystals are hard and brittle because they are made up of atoms that combine by ionic bonding.

• An iron nail has a reddish color because iron atoms on its surface combine with oxygen atoms.

• A vegetable has a bitter taste because some of the compounds that make it up are bases.

Which two options describe physical properties of matter?

• The amount of mass per unit volume

• How easily a substance reacts with other substances

• The color of the light that is reflected off a substance's surface

• Whether a substance is acidic or basic

• Whether a substance forms a patina

Which statement accurately describes malleability?

• A liquid with larger molecules resists movement more than a liquid with smaller molecules does.

• Attractive forces between molecules at the surface cause a liquid to resist spreading out.

• A material slows or completely blocks the flow of electrons through it.

• A material with relatively weak bonds between its particles can be shaped into a thin sheet.

Why is an ice cube less dense than liquid water?

• Molecules in ice are more spread out than molecules in liquid water

• Ice molecules have less mass than water molecules.

• Ice molecules have more mass than water molecules.

• Molecules in ice have less space between them than molecules in liquid water.

Which materials allow electrons to flow through them?

• Semiconductors and insulators

• Semiconductors and conductors

• Conductors only

• Insulators only

Which type of force is the weakest?

• Van der Waals forces

• Metallic bonds

• Hydrogen bonds

• Ionic bonds

Which statement compares the attractive forces that hold particles together?

• Metallic and covalent bonds are weakly attractive; hydrogen bonding and Van der Waals forces are strongly attractive.

• Metallic bonds and Van der Waals forces are weakly attractive; covalent and hydrogen bonds are strongly attractive.

• Metallic and covalent bonds are strongly attractive; hydrogen bonding and Van der Waals forces are weakly attractive.

• Covalent bonding and Van der Waals forces join molecules together; ionic and hydrogen bonding produce compounds.

Which factor has the most significant influence on a liquid's surface tension?

• The chemical reactivity of its atoms

• The mass of the substance

• The strength of the electric forces between its molecules

• The pH of the substance

A molecule of water, H₂O, and a molecule of methane, CH₄, have close to the same mass. Which statement explains why water has a much higher boiling point than methane?

• There is hydrogen bonding between methane molecules.

• There is ionic bonding between water molecules.

• There is ionic bonding between methane molecules.

• There is hydrogen bonding between water molecules.