Presentation on theme: "MATTER: is defined as anything that takes up space and has mass. Examples of matter include all the elements, compounds, mixtures, cow’s milk and store."— Presentation transcript:
Matter changes from one phase to another by these processes... MELTING FREEZING BOILING CONDENSATION SUBLIMATION DEPOSITION Boiling water vaporizes into steam Sublimation is when a solid goes directly to the gas phase, and deposition is the opposite. In our class you will see solid iodine sublimate to a fantastic purple gas, and some of it will undergo deposition and form back into solid iodine again. Solid to liquid Liquid to solid Liquid to gas Gas to liquid
Depending upon who is counting, there are approximately 114 unique substances known to man at this time. They are the building blocks of all substances we know of. They are listed in the PERIODIC TABLE OF ELEMENTS. Atoms are the smallest part of an element. Examples include CARBON, HYDROGEN, NITROGEN, and OXYGEN. Your teacher’s favorite element is MERCURY and he also really likes TUNGSTEN.
When two or more elements combine chemically to form a new substance, with its own UNIQUE physical and chemical properties, the new substance is called a compound. Examples of common compounds include: TABLE SALT (sodium chloride) BUNSEN BURNER GAS (methane) and WATER (dihydrogen monoxide)
ALL MATTER MIXED SUBSTANCES PURE SUBSTANCES physically separable into (HOMOGENEOUS)(VARIED COMPOSITIONS) COMPOUNDS ex: water, salt, iron oxide ELEMENTS: iron, neon, mercury, lead, carbon. HETEROGENEOUS MIXTURES ex: SOUP, SALAD, CONCRETE, COW’S MILK HOMOGENEOUS MIXTURES ex: coffee, air, STORE MILK. chemically separable into
IRON becomes RUST… This is a chemical reaction. The iron and oxygen are the reactants, which chemically combine into a new substance with new properties. RUST forms, which is a kind of IRON OXIDE. The iron oxide is the PRODUCT of this chemical reaction
REACTANTS COMBINE TO FORM PRODUCTS Another chemical reaction you probably know of is called photosynthesis. In this reaction carbon dioxide and water combine to form oxygen and glucose. The reactants are the carbon dioxide & water. The products are oxygen and glucose.
Matter Cannot Be Created Nor Destroyed in any PHYSICAL or CHEMICAL CHANGE. In every case, the mass of the reactants equals the mass of the products.
Match the element name with its symbol sodium potassium magnesium chlorine oxygen carbon iron helium calcium sulfur aluminum Cl O He Ca S K Fe Mg Al Na
Match the element name with its symbol sodium - Na potassium - K magnesium - Mg chlorine - Cl oxygen - O carbon - C iron - Fe helium - He calcium - Ca sulfur - S aluminum - Al Not all of the symbols match up to the first letters of the element names because many elements are named from other languages. Practice the symbols, or look them up – NEVER GUESS !
In the chemical reaction of the combustion of methane with oxygen (what happens on your stove or Bunsen burner), carbon dioxide and water are produced and heat is given off. Label the reactants and products in the word, and the balanced chemical equations below. methane + oxygen carbon dioxide + water + heat
Since it is the REACTANTS that combine to form PRODUCTS it should be clear already that the… the REACTANTS ARE: methane and oxygen the PRODUCTS ARE: carbon dioxide & water HEAT is also given off during this reaction. Heat is a product, but it has no mass. methane + oxygen carbon dioxide + water + heat REACTANTS PRODUCTS reactants chemically combine into products
Two types of Mixtures Mixtures are when two or more pure substances (elements or compounds) are physically mixed together. They retain their properties, they do not chemically combine. They can mix perfectly together (like chocolate sauce and milk) or not so well (like salt and nickels). Mixed perfectly the mixture is said to be HOMOGENEOUS, the same throughout. If the mixture is not mixed the same throughout is called HETEROGENEOUS. Fresh chocolate milk is homogeneous, but if you let it sit too long, the chocolate settles to the bottom, making the mixture heterogeneous.
Which of these mixtures are homogeneous, which are heterogeneous? split pea soup apple sauce Mint chocolate chip ice cream tap water coffee with cream saltwater IV glucose solution Elmer’s glue motor oil Oatmeal raisin cookie dough Early Chemists describe the first DIRT MOLECULE. (from the Far Side)
split pea soup………… homogeneous apple sauce……………. homogeneous Mint chocolate chip ice cream….. heterogeneous tap water……………….. homogeneous coffee with cream…. homogeneous saltwater……………… homogeneous IV glucose solution… homogeneous Elmer’s glue………….. homogeneous motor oil……………… homogeneous Oatmeal raisin cookie dough……….. heterogeneous homogeneous or heterogeneous?
Hydrogen and oxygen react chemically to form water. How much water is formed if exactly 4.8 grams of hydrogen combines completely with 38.4 grams of oxygen? ____ If 28.0 grams of nitrogen will combine chemically with hydrogen, to form 34.0 grams of ammonia (ammonia = NH 3 ) exactly how many grams of hydrogen are required for this reaction? ___ If 24.0 grams of carbon chemically combine with 2.0 grams of hydrogen to form acetylene, how many grams of acetylene is made? ___ all three answers at the END of slide show
Mixtures are physical blends of matter. Mixtures are not chemical compounds. Mixtures retain the properties of the substances that are in them. They can be separated by physical means. The different physical properties of the matter are used to separate them (such as Boiling and Freezing Points, and Density). Go slowly through the next few slides and THINK.
Distillation apparatus: what’s it for & how does it work? In the round bottomed flask at left is a MIXTURE, for instance it is SALT WATER. The salt is mixed into the water, but it is not a new chemical compound. Because the salt and the water have different physical properties specific to their kind of matter, we can use this difference to separate them physically using their different boiling points.
Distillation apparatus: what’s it for & how does it work? Heating the salt water to 102ºC, the water boils into steam. The salt would require MUCH MORE heat to vaporize, so as the steam escapes out the top of the tube and goes into the condenser tube, the salt is left behind in the round bottomed flask. The MIXTURE IS NOW SEPARATED. Using differences in physical properties to separate a mixture.
Distillation apparatus: RESULTS The law of conservation of matter says: Matter cannot be created or destroyed in any physical or chemical process. If you started with 120 grams of salt water (made from 100 grams of water and 20 grams of salt), You end up with 100 grams of water in the flask at right, and the 20 grams of salt get left behind in the round bottomed flask.
Distillation apparatus: RESULTS You use the difference between physical properties, such as boiling point in this case, to separate mixtures with physical means. This could work for ANY two or more substances you put into the round bottomed flask, that had different boiling points. For example, this is how you separate gasoline from crude oil using the different boiling points for each kind of oil product.
You can separate iron filings from sand just by using a magnet. The mixture is just a blend of different kinds of matter. You can separate a mixture with a physical method this simple.
FILTERS can separate mixtures too, but they can only remove solids from liquids. Here it looks liked chopped KIWI fruit is being filtered and only Kiwi Juice will end up in the beaker. Mixtures like salt water, or coffee (which are both SOLUTIONS) cannot be filtered apart, you need the distillation apparatus.
Paper Chromatography is another way to separate mixtures from each other. Putting drops of colored ink from markers onto filter paper and then allowing the water to flow through the paper will result in the inks being separated in to the different colors that blend together to make the colors. Most single color markers are really mixtures of several colors. water
Soon the water flows upwards and separates out the different colors of ink that make up the mixture of colors that appears blue to our eyes. The colors breaking into rainbows above left is what will happen to the color dot at right as the water flows through it. The water will separate the colors of the mixture and the least dense colors will move the furthest. Chromatography is another way to separate mixtures from each other using different densities of colors to move fast or slow through filter paper. water flows up
Hydrogen and oxygen react chemically to form water. How much water is formed if exactly 4.8 grams of hydrogen reacts completely with 38.4 grams of oxygen? 43.2 grams If 28.0 grams of nitrogen will combine chemically with hydrogen, to form 34.0 grams of ammonia (ammonia = NH 3 ) exactly how many grams of hydrogen are required for this reaction? 6.0 grams If 24.0 grams of carbon chemically combine with 2.0 grams of hydrogen to form acetylene, how much acetylene is made? 26.0 grams