Post on 27-Dec-2015
3/14 p.42 Physical and Chemical properties IQ: Identify the substances below using their properties:
Sugar, Sand, Cotton, IronSubstance A:B:C:D:
What is matter?! It is the stuff that everything is made of.
oBased on arrangement of atoms/particles.
What Does That Mean?• Mass is the amount of material
something has in it.oMeasured in grams (g).oMeasured with a tool called a triple beam balance.
AKA: ‘3 beamer’
• Volume: the amount of space something takes up oMeasured in liters (L) for liquids & cubic
meters (m3) for regular solids.
o Something like a rock would be measured in milliliters (mL), because you drop it in a GC & see how much H2O rises. Water displacement
o 1mL=1cm3
Phys. Vs. Chem. Properties video (2:28)
Physical Properties
A physical property of matter can be observed or measured without changing the identity of the matter. For ex: we can still see an apple is an apple, even after
it’s sliced.
Matter has specific & general properties:
• General - relates to ALL matter; allows ID as matter– Ex: mass, volume, weightDepend upon how much of the substance you
have.
• Specific - relates to ONE type of matter; UNIQUE to each kind of substance– Ex: color, shape, hardness, density
Do NOT depend upon how much of the substance you have.
Physical Properties of MatterCommon physical properties used to describe matter
include:
Density SolubilityMelting Point Boiling PointMalleability DuctilityConductivity Luster
Density – the amount of matter in a given space or volume (m/v). Lead is denser than water, so it sinks. Cork is less dense than water, so it floats.
o REMEMBER: Density of water is 1.0 g/cm3.
Solubility - the ability of a substance to dissolve into another substance Ex: Sugar dissolves in water
oSOLUTE: the thing that is being dissolved (sugar)oSOLVENT: the thing causing/doing the
dissolving (water) Water is known as the universal solvent
Can dissolve almost anything w/enough time!
Melting Point - the temp. @ which a substance changes from a solid to a liquid. Ex: melting point of ice is 0oC.
Boiling Point - the temp. @ which a substance changes from a liquid to a gas Ex: the boiling point of water is 100oC.
Question
• Does the amount of water we have affect its melting point? Boiling point?
• So is it a general or a specific property?
Malleability - the ability of a substance to be pounded into thin sheets
Ex: aluminum foil/cookie sheets
Conductivity - the ability of a material to move heat or electricity
Ex: iron is a good conductorof heat & electricity, whileStyrofoam isn’t. It would be called an insulator.
Magnetism – the ability of a substance to attract iron or objects containing iron. Also, cobalt and nickel.
Chemical Properties:
Chemical properties describe a substance’s ability to change into a new substance with entirely different properties.
Chemical properties include:
Flammability – the ability of a substance to burn.
Or CombustibilityEx: wood is flammable (after burning completely, new substances are formed), but gold is not
Reactivity – the ability to react with other substances, such as water, acid, or oxygen.
Ex: baking soda reacts with vinegar to produce entirely new substances with totally different properties.
Acidity – the ability to react with a base to neutralize their properties and produce salts.
Ex: HCl (hydrochloric acid) reacts with NaOH (sodium hydroxide) to produce H2O (water) and NaCl (salt).
Measured on a phScale, water is Neutral, ph 7. Acidslower, bases higher.
Study jams animation
3/12/14Pg 38 Density Lab
IQ:If you take a Twix candy bar &
break it in half, will the density of each half bea.The same as the originalb.Greater than the originalc.Less than the originalExplainDensity
Chemical properties - Examples• Examples of chemical
properties include:– The ability to burn– Ability to tarnish– Ability to rust– Ability to decompose– Ability to react with other
chemicals– Instability– Ability to do acid/base
reactions
Chemical and physical properties – So what?
• Titanium is very strong and doesn’t rust, so it is often used in jet engines.
• Titanium is also nonallergenic. This, combined with the fact that it is rust proof makes it great for artificial joints as well as piercings.
Chemical and physical properties – So what?
• Tungsten is usually used as the filament in lightbulbs because it has the highest melting point of any metal.
• It glows red hot when electricity runs through it, and it gives off both heat and light.
Chemical and physical properties – So what?
• Vanadium is heavier and harder than titanium, so mixing a tiny bit of vanadium with steel can make cheap tools that are still very strong.
Chemical and physical properties – So what?
• Helium is almost completely nonreactive (inert).
• It is lighter than air, so it’s great for floating balloons (or making funny voices.)
• When electricity runs through helium, it glows a creamy pale peach color.
Chemical and physical properties – So what?
• In 1943, all US pennies were made of zinc plated steel because copper was being used in the war. The pennies had to be coated with zinc because steel will rust, but zinc won’t.
Chemical and physical properties – So what?
• Sulfur smells awful. Rotten eggs, onions, and garlic all have sulfur in them. Stink bombs use sulfur to create a bad smell.
• Sulfur is also flammable, and it is one of the 3 main ingredients in gun powder.
Chemical and physical properties – So what?
• Chromium is famous for its intense luster. Chrome plated tools, jewlery, silverware, or car parts are very popular.
Chemical and physical properties – So what?
• Most bullets are made of lead because lead is a very dense metal. These bullets are required, by international law, to be coated with a different metal because lead has such a low melting point and is so malleable.
Chemical and physical properties – So what?
• The most dense elements are Iridium and osmium which have a density of about 22.6 g/cm3
• OQ: Classify as chemical or physical properties:
1. A sample of sulfur weighs 20 grams.
2. Hydrochloric acid forms H ions in water.
3. Copper is shiny red and tarnishes in air.
4. Neon does not form compounds.