Chemical and physical properties
Face (shape, expressions) All substances have properties Example: Including people! People can be identified by their Voice Height Finger prints Eye color Hair color Teeth DNA
What are properties? Matter has observable and measurable qualities. We can use general properties to identify substances. All matter has 2 types of properties: Physical properties and chemical properties.
Physical properties A physical property is a characteristic of a substance that can be observed without changing the substance into another substance. (You can see it without changing what you re looking at into something else.)
Physical Properties Physical properties can be extensive or intensive: Extensive properties depend on the amount of a substance that you have. (measurable) Intensive properties don t depend on how much you have. Examples of extensive physical properties include: Volume Mass Weight Size Examples of intensive physical properties include: Density Melting point Boiling point
Physical Properties - Examples Other physical properties include: Color Hardness Odor Taste State of matter Texture Luster (shine) Flexibility Heat conductivity Electrical conductivity Solubility (ability to dissolve in water.) Shape Viscosity Ductility Malleability
Let s review Mass- the amount of matter in an object Ex. A bowling ball has more mass than a ping pong ball. Volume- is the amount of space that matter takes up. Ex. The Atlantic Ocean holds a larger volume of water than a gallon container. So.. What s density? Density is the amount of mass in a given volume. In other words, how much stuff in a certain amount of space. Which is more dense, a tennis ball or a bowling ball?
Density is found my finding the mass (g) and dividing it by the volume (cm 3 ). Formula for density Density= mass/volume or D=m/v Density Density dilemma!!! Both have the same volume Volume= 100 cm 3 (cubic centimeter) Ball A: 200g D=200g/100cm 3 = 2g/cm 3 Ball B: 150g D=150g/100cm 3 = 1.5g/cm 3 BALL A IS MORE DENSE
How do we find the volume? Scientists use different ways to calculate the volume of an object. One way is by using a graduated cylinder to observe how much water is displaced (moved) by the object. Ex. Fill the cylinder with 20mL of water and place the object inside. The water level raises to 25 ml. 5mL of water has been displaced (25-20) which means the volume of the object is 5mL. Find the density of the object if the mass was 15g. Density= 15g/5mL= 3g/mL
Density The property of density can help us determine the substance. Known: Gold has a density of 19.3 g/ml Unknown substance Mass: 50g It displaced 10mL of water. What s the density? Is this gold? It s actually pyrite fools gold! It has a density of 5g/mL
State of matter-observable features Solid, liquids and gases This property of matter is affected by temperature and pressure. Ice= water in solid state Water= water in liquid state (ocean/clouds) Vapor= water in gaseous state. Each molecule is the same, 2 H & 1 O.
Boiling Point/Melting Point The temperature at which a substance changes from a liquid to a gas is called the boiling point. The boiling point of water is 212 degrees F or 100 degrees Celsius The temperature at which a substance changes from a solid to a liquid is called the melting point. Melting point of water 0 degrees Celsius We ll be checking the melting and boiling points of other substances soon
List as many physical properties as you can for this item Physical properties
A Chemical property is a characteristic of a substance that can only be observed by changing it into a different substance. Chemical properties
Chemical properties - Examples Examples of chemical properties include: The ability to burn or set to fireflammability/combustibility Ability to tarnish-lose luster (shininess) Ability to rust (oxidation) Ability to decompose(to break down) Ability to react with other chemicals Instability- substance being unstable; breaking and down and releasing toxins,etc.
Cool chemical reactions https://www.youtube.com/ watch?v=0kfaoqodzok
List as many chemical properties as you can for this item. Chemical properties
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. Has a low reactivity--- rusting. Luster- jewelry.
Chemical and physical properties So 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. No combustion/flammability-- what?
Chemical and physical properties So 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. Malleable Durable what?
Chemical and physical properties So 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. what?
Chemical and physical properties So 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. what?
Chemical and physical properties So 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. what?
Chemical and physical properties So Chromium is famous for its intense luster. Chrome plated tools, jewlery, silverware, or car parts are very popular. what?
Chemical and physical properties So The most dense elements are Iridium and osmium which have a density of about 22.6 g/cm3 what?
Using chapter 5 section 1&2 Physical Property Create a chart writing down the differences and examples of both chemical and physical properties Include at least 3 examples and a drawing Chemical Property