Benchmark Review 2016

Accurate measurement When measuring distance: You must measure accurately and precisely. Base measurements - Meters,(length) Liters (liquid), Grams (mass)! Use Metrics!!!

When measuring liquids: Use a graduated cylinder. Beakers are not accurate!!! Read the bottom of the meniscus (curved line formed by the water) on a graduated cylinder. Check your units. Do they increase or decrease? Do they go up by 1.0, 0.1, or 5.0? Read carefully.

When determining mass: Use a Triple Beam Balance. Volume of irregular objects: Use a graduated cylinder to take volume by water displacement.(difference between initial reading and final reading)

Density is defined as the mass of a substance divided by its volume. D = m/v More dense liquids will sink in the presence of less dense liquids. Density of water=1.0

Reading Graphs and Making Calculations Analyze graphs or do basic math calculations to solve problems or draw conclusions. Dependent variable is on the Y-axis. The Independent Variable on a graph is on the X-axis. (DRY/MIX)

Line graphs represent change over time Line graphs represent change over time. The steeper the slope of a line, the faster the change in time is occurring.

Remember to use your triangles! The formulas are on the back of the periodic tables.

Newton’s Laws of Motion

Measureing Newtons with a Spring Scale The surface depends on how many newtons you will use!

Acceleration and Velocity Acceleration is changing speed OR direction. Results from unbalanced forces. Any change in direction is also a change in Velocity Velocity is speed with a given direction. 500 N 400 N

Potential and Kinetic Energy Potential Energy is stored energy and is determined by position. Kinetic Energy is energy of motion and is determined by speed. As Potential Energy increases Kinetic Energy decreases. Usually the higher up an object is, the more potential energy it has.

Nucleus-protons/neutrons =dense, positive charge Atoms are the basic unit of chemistry. They consist of 3 smaller particles: Protons - these are positively charged (+) (Atomic Number) Mass -1 amu – THESE IDENTIFY THE ATOM!! Electrons - these are negatively charged (-) Mass 1/1800th amu Neutrons - have no charge- 1 amu Nucleus-protons/neutrons =dense, positive charge Electron cloud/Rings = Electrons-negative-almost no mass.

Sodium-23 mass number

Elements and Compounds Elements are the purest form of a substance. They are represented on the periodic table. Examples- H, H2, He, O, O2 , etc. Compounds are two or more different elements combined chemically. Examples – H2O, NaCl, CO2, etc.

Properties of Metals: luster, ductile, malleable (not brittle), good conductors of heat and electricity. Metals

Law of Conservation of Mass Mass is neither created nor destroyed during chemical or physical reactions. Total mass of reactants = Total mass of products Antoine Lavoisier

Periodic Table Arrangements Horizontal rows are called periods. Vertical columns are called groups or families and have the most similar properties. Valence Electrons are the electrons on the outermost ring = REACTIVITY!!! Elements in SAME group will react similarly.

The Law of conservation of mass states that matter cannot be created or destroyed in any chemical reaction The bonds between atoms in the reactants (left) are rearranged to form new compounds as products (right), but none of the atoms disappear, and no new atoms are formed. So: Chemical equations must be balanced, meaning the numbers and kinds of atoms must be the same on both sides of the reaction arrow. The numbers placed in front of molecules to balance equations are called coefficients, and they multiply all the atoms in the chemical formula.

Labels of a Chemical Equation subscripts YIELDS 3 Molecules 2 Molecules 2 Elements 2 Elements H-4 H-4 O-2 O-2

Organic Compounds Remember – Carbon is the most important If asked to identify the Organic Compound look for C

Physical vs Chemical

Energy Transformations

Remember to read carefully and work out your problems completely Test Strategies Remember to read carefully and work out your problems completely