Objectives PSc.2.1.3 Compare physical and chemical properties of various types of matter.

Physical Properties Physical properties are characteristics that a sample of matter exhibits without any change in its identity. This property can be observed and measured without changing the identity of the substance.

Physical Properties Examples of the physical properties of a chunk of matter include its: boiling point solubility density melting point magnetic color electrical conductivity and physical state (solid, liquid or gas)

Physical Properties Salt is soluble in water. Water boils at 100°C.

Chemical Properties Chemical Properties are properties of matter that describes a substance’s ability to participate in chemical reactions. A chemical property describes how a substance changes into a new substance, either by combining with other elements or breaking apart into new substances.

Chemical Properties Examples: Reactivity- the ability of a substance to combine chemically with another substance. Flammability- the ability of a substance to react in the presence of oxygen and burn when exposed to a flame. In general, the ability of a substance to react…to form…

Chemical Properties You can observe chemical properties only in situations in which the identity of the substance changes.

Physical vs. Chemical Prop. Classify the following properties as either chemical or physical. red color density flammability solubility reacts with acid to form hydrogen supports combustion bitter taste melting point reacts with water to form a gas reacts with a base to form water hardness boiling point can neutralize a base luster odor

Physical vs. Chemical Prop. Physical Properties Red color Density Solubility Bitter taste Melting point Hardness Boiling point Luster Odor Chemical Properties Reacts with acid to form hydrogen Supports combustion Reacts with water to form a gas Reacts with a base to form water Can neutralize a base

Density Density is the amount of matter (mass) contained in a unit of volume. Styrofoam has a low density or small mass per unit of volume.

Density m V D

m V D Density Solving Density Problems Cover the variable you are solving for If you cover the top variable, multiple the bottom ones V m D To solve for mass, multiply volume by density.

m V D Density Solving Density Problems Cover the variable you are solving for If you cover a bottom variable, take the top variable and divide by the bottom V m D To solve for volume, take mass and divide by density.

V D m = V x D V= 5.0 mL m = (19 g/mL) (5.0 mL) m = ? m = 95 g m Calculate the mass for an object having a density of 19 g/mL and a volume of 5.0 mL. GIVEN: D = 19 g/mL V= 5.0 mL m = ? WORK: m = V x D m = (19 g/mL) (5.0 mL) m = 95 g V m D

V D V = m ÷ D V = (18 g) ÷ (12 g/mL) V = ? V = 1.5 mL m m = 18 g Calculate the volume for an object having a mass of 18 g and a density of 12 g/mL. GIVEN: m = 18 g D = 12 g/mL V = ? WORK: V = m ÷ D V = (18 g) ÷ (12 g/mL) V = 1.5 mL V m D

Density Solve the following density problems. 1. The density of sugar is 1.59 g/cm3. Calculate the mass of sugar in 15.0 mL. (1 mL = 1 cm3) 23.9 g

Density 2. The density of helium is 0.178 g/L. Calculate the volume of helium that has a mass of 23.5 g. 132 L

Density 3. A 14.95 g sample of gold has a volume of 0.774 cm3. Calculate the density of gold. 19.3 g/cm3

Density 4. Balsa wood has a density of 0.12 g/cm3. What is the mass of a sample of balsa wood if its volume is 134 cm3? 16 g

Density 5. The density of ice at 0 °C is 0.917 g/cm3. Calculate the volume of 145 g of ice. 158 cm3

Quiz Melting point Boiling point Density Reactivity Flammability The temperature at which a solid becomes a liquid. Ability of a substance to burn in the presence of oxygen. Ability of a substance to combine chemically with another substance. Mass per unit volume of a substance. Melting point Boiling point Density Reactivity Flammability