States, Boiling Point, Melting Point, and Solubility Solid Liquid Gas 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 Particle View of a Solid ● Particles in a solid are PACKED CLOSELY together and they are in a FIXED POSITION. Particles vibrate in place 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). 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. 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 Increase Thermal Energy (Heat up) point Solid Liquid Gas Melting Melting Boiling Point 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 Liquid Gas 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 Increase Thermal Energy (Heat up) Solid Liquid Gas Decrease Thermal Energy (Cool off) Melting & Boiling Point Melting Boiling Gas turns back into a Point Point liquid at its boiling point because it’s moving in the OTHER DIRECTION. Metal becomes a liquid just above its Increase Thermal Energy (Heat up) melting point. Solid Liquid Gas Decrease Thermal Energy (Cool off) Boiling Point Increase Thermal Energy (Heat up) ● Particles move the least under melting point (as a solid). Solid Liquid Gas ● Tin is a metal. Describe the movement of particles AFTER Decrease Thermal Energy (Cool off) boiling point of Tin. ● The higher the boiling point, the more energy Which one required to boil! requires the most energy to boil? Boiling Point and Melting Point Boiling point Melting point Solubility ● Maximum amount of a substance that can be dissolved in a liquid (at a specific temperature). ● Soluble means it will dissolve. Insoluble means it will NOT dissolve. ● Stirring SPEEDS UP the dissolution process because you are increasing the movement and the energy of the particles. The War of Insolubility! Solubility can change… ● Increased Temp = Increased Solubility ● Different substances have different solubility curves NaCl Dissolving in H2O.