Presentation on theme: "MIDTERM REVIEW WORKSHEET OPEN BOOK 30 POINT QUIZ To Be Turned in at your Midterm."— Presentation transcript:
MIDTERM REVIEW WORKSHEET OPEN BOOK 30 POINT QUIZ To Be Turned in at your Midterm
Components of an Experiment Independent Variable: The factor in the experiment that is purposely changed. “I” the examiner change Dependent Variable: Measurable factor that responds to a change in the independent variable. Dependent depends on the independent. Constant- Conditions that remain the same during the course of the experiment Control- A standard for comparison, not in every experiment.
**Remember how to choose the Independent variable (what “I” the examiner change), Dependent variable (depends on the independent- usually measurable), Constants (remains the same), Control (standard to compare to) etc.
MATTER PURE SUBSTANCE MIXTURE Matter that has a fixed composition (makeup) and definite properties (chemical and physical). Matter that is a combination of two or more pure substances that do not have a fixed composition or definite properties. Are chemically combined- so they can’t be physically separated. Are NOT chemically combined, so components CAN be separated.
Compound: A substance made of atoms of 2 or more different elements that are chemically combined.
Element: A substance that can’t be broken down into simpler substances Each element is made of only one kind of atom.
ATOM: The smallest unit of an element that maintains the properties of the element.
MOLECULE: H 2 O O 2 The smallest unit of a substance that behaves like the substance. (Keeps all of its physical and chemical properties)
PHYSICAL CHANGE Dissolving Sanding Crushing Breaking/cutting Bending/twisting Mixing CHANGE OF STATE – Melting/evaporating – freezing A change of matter from one form to another without a change in chemical properties
CHEMICAL CHANGE ODOR COLOR CHANGE BUBBLING FIZZING FOAMING HEAT PRODUCED SOUND PRODUCED A change of matter that occurs when a substance changes composition by forming one or more new substances CANNOT BE REVERSED BY PHYSICAL CHANGES
Boyle’s Law, Charle’s Law of Gases: Constant Temperature: If you decrease the volume you will increase the pressure. Constant Pressure: If you increase the temperature the volume will increase (if it could).
Bohr’s Model of the Atom Like planets around the sun
ATOMIC NUMBER = Number of Protons = Number of Electrons
MASS NUMBER = (Atomic Mass, Atomic Weight) Number of Protons + Number of Neutrons Atomic Number + Number of Neutrons
Using the Periodic Table ELEMENT NAME AND SYMBOL ATOMIC # MASS NUMBER (round to nearest whole number) NUMBER of PROTONS NUMBER of NEUTRONS NUMBER of ELECTRONS NUMBER of VALENCE ELECTRONS OXIDATION NUMBER and CHARGE (+ or -) (P)15 38 Gallium (Ga) 31
Using the Periodic Table ELEMENT NAME AND SYMBOL ATOMIC # MASS NUMBER (round to nearest whole number) NUMBER of PROTONS NUMBER of NEUTRONS NUMBER of ELECTRONS NUMBER of VALENCE ELECTRONS OXIDATION NUMBER and CHARGE (+ or -) Phosphorus (P) Strontium (Sr) Gallium (Ga) 31703139313+3 Remember: Atomic number is = the number of Protons In a Neutral Atom the number of = protons is = to the number of – electrons All the Mass in in the nucleus- The Mass Number is = Protons + Neutrons Valence Electrons = outer shell = Group 1 has 1, Group 2 = 2, Group 13 = 3, Group 14 = 4 etc Oxidation # = # of electrons taken in (-) or give away (+) to get to a full valence shell.
Dalton's Atomic Theory 1) All matter is made of atoms. Atoms are indivisible and indestructible. 2) All atoms of a given element are identical in mass and properties 3) Compounds are formed by a combination of two or more different kinds of atoms. 4) A chemical reaction is a rearrangement of atoms.
This chart and a Periodic Table will be provided to you- you just have to know how to READ it and USE it. Practice with your class worksheets, quizzes and homeworks
Organic Compound A COVALENTLY bonded compound that contains carbon Most common elements: C,H ANY organic compound that is burned will release Carbon in some form
Hydrocarbon An organic compound made of only carbon and hydrogen Simplest Hydrocarbon: Methane
Alkanes, Alkenes, Alkynes Only Single Bonds C-C At least one Double C=C At least one Triple C=C
POLYMERS Polymers are substances that are made up of a large number of repeating units (monomers). There are both synthetic and naturally occurring polymers. Formed by chemical reactions in which these monomers are joined in a certain order, forming a chain.
Natural Polymers: ProteinsProteins - silk, collagen, keratin, DNA Repeating units of amino acids Carbohydrates - cellulose, starch. Made up of repeating units of glucose Carbohydrates Other Natural polymers: Rubber (hydrocarbon base) and silicones (alternating silicon and oxygen).
Cross Linking of Polymers: Cross linking: Makes the polymer elastic, flexible by helping it to go back to its original shape after stretching. Too many cross links and the polmer becomes rigid (like the back of a desk chair), or may even crack/break
Counting Atoms 2H 2 O = 2 Molecules of H 2 O, or 4 atoms of H, 2 atoms of O, 6 atoms all together Co