States, Boiling Point, Melting Point, and Solubility Solid Liquid Gas

Questions What are the 3 states of matter? Write a definition for each state?

Defining States of Matter States of matter are NOT defined by what they are made of. Example: solids can be elements (gold), compounds (Salt = NaCl), or mixtures (butter) Element (Au) Compound (NaCl) Mixture (Milk, Salt, etc)

Defining States of Matter States of matter are defined by whether they hold SHAPE and VOLUME Element (Au) Compound (NaCl) Mixture (Milk, Salt, etc) ALL KEEP THE SAME SHAPE AND VOLUME = Solids

Defining States of Matter Solids – have a definite SHAPE and VOLUME. Element (Au) Compound (NaCl) Mixture (Milk, Salt, etc) ALL KEEP THE SAME SHAPE AND VOLUME

Particle View of a Solid Particles in a solid are PACKED CLOSELY together and they are in a FIXED POSITION. Particles vibrate in place This fixed, closely packed arrangement causes a solid to have a definite shape and volume

Liquids Liquids – has definite VOLUME but no defined SHAPE 100 ml

Particle View of a Liquid Packed CLOSELY (like a solid), but move FREELY around each other (must stay in contact). Because liquid particles are free to move, a liquid has no definite shape. However, it does have a definite volume.

Gases Gases - do NOT have definite SHAPE or VOLUME. Bromine gas fills up the entire volume of the container

Particle view of a Gas Particles can MOVE FREELY and will either fill up or squeeze into available space.

Questions 1) Which Statement is True? A) Liquids have a definite shape and volume B) States of matter are defined by the substances they are made up of C) Gases have a definite shape and volume D) Solids have a definite shape and volume

Task Draw a diagram of A) Gas particles B) Liquid particles C) Solid particles

Changes in States of Matter Thermal Energy – heat energy. More thermal energy = More particle movement

Changing States Solid Gas Liquid Increase Thermal Energy (Heat up) Decrease Thermal Energy (Cool off)

Melting point Melting - change from solid to liquid Melting point - SPECIFIC temperature when melting occurs. Each pure substance has a SPECIFIC melting point. Examples: M.P. of Water = 0°C (32°F) M.P. of Nitrogen = -209.9 °C (-345.81998 °F) M.P. of Silver = 961.93 °C (1763.474 °F) M.P. of Carbon = 3500.0 °C (6332.0 °F)

Melting Point Particles of a solid vibrate so fast that they break free from their fixed positions. Increasing Thermal Energy Solid Liquid Melting point

Vaporization Vaporization – change from liquid to gas Vaporization happens when particles in a liquid gain enough energy to form a gas. Increasing Thermal Energy Gas Liquid Boiling point

Two Kinds of Vaporization Evaporation – vaporization that takes place only on the surface of the liquid Boiling – when a liquid changes to a gas BELOW its surface as well as above.

Boiling Point Boiling Point – temperature at which a liquid boils Each pure substance has a SPECIFIC boiling point. Examples: B.P. of Water = 100°C (212°F) B.P. of Nitrogen = -195.79 °C (-320.42 °F) B.P. of Silver = 2162 °C (3924 °F) B.P. of Carbon = 4027 °C (7281 °F)

Boiling Point and Melting Point

Solubility Maximum amount of a substance that can be dissolved in a liquid (at a specific temperature). Salt (NaCl) Water (H20) at 20°C

Solubility Solute – substance being dissolved Solvent – liquid substance that solute is dissolved into Salt (NaCl) Water (H20) at 20°C

Solubility Salt Water Solute – ?????? Solvent – ????? Water (H20) Salt (NaCl) Water (H20) at 20°C

Solubility can change Increased Temp = Increased Solubility Different substances have different solubility curves