Measurement Matter and Density. Name: Period:

Transcription

1 Measurement Matter and Density Name: Period:

2 Studying Physics and Chemistry Physics Tells us how fast objects move or how much it takes to get objects to, turn or stop. Chemistry Explains how different kinds of are created and how matter can be from one kind to another. Energy Measures the ability for things to. Energy is exchanged when changes. Nothing changes when no energy is exchanged. The is the of energy for Earth. The Physical Science in Your Life amount of stuff (matter) an object contains. everything that has mass and takes up space. of matter the different forms matter can take: solid, liquid, gas or plasma. change- a of, but not a change in the type of matter you have. Phases (states) of matter are physical changes. change a change that transforms of matter into kind (or several) which may have different properties. Measurement Units in the system are based on multiples of, Distance - amount of between 2 points (m)-basic metric unit of length. Units of length: millimeters ( ), centimeters ( ), kilometers( ), astronomical unit ( ), light year. Converting Between Units (Dimensional Analysis) To convert between units, we use factors A conversion factor is a ratio that has the value of 1. (numerator = ) 1 minute 1 yard 1 cm 1000 m 100 cm 60 sec 3 feet 10 mm 1 km 1 meter distance between Earth & sun -light travels in 1 year (9.5 trillion km) Time-- A is the basic unit of time in the system. Units of time: seconds, minutes, hours Sample: Convert 3 minutes into seconds. 3 minutes 60 seconds = 180 seconds 1 1 minute 1

3 Converting Between Metric Units To convert from one unit to another in the system you will multiply or divide by a power of. (10, 100, 1000 ) This is accomplished by simply the. When converting from a smaller unit to larger unit, you will get fewer of the larger unit. Therefore, you must divide or move the decimal point to the left in such a case. # up=# the left When converting from a larger unit to smaller unit, you will get more of the smaller unit. Therefore, you must multiply or move the decimal point to the right in such a case. # down=# the right Variables and Relationships - a quantity that has a value which describes something: mass, time, position, angle, temperature the particular (with units) or choice that a variable may have. Example: Jim was 1.23 meters tall. What is Jim s height in centimeters? (2 steps down therefore 2 decimal places to the right) 1.23 meters x (100 centimeters/meter) = centimeter = 123 cm The color represents all possible choices and is a, a specific choice of color. 2.1 Graphs a mathematical that shows a relationship between variables. Two variables may have: Weak relationship No relationship Strong relationship between variables between variables between variables. Dependent versus Independent Variable variable change (x-axis) variable shows of the change (y-axis.) A graph makes it easy to see if a change in one variable changes in the other variable (the effect).

4 Four steps to making a graph Step 1: Determine which is the dependent and independent variables. The dependent variable goes on the and the independent variable goes on the Step 2: Make a scale for each axis by counting boxes to fit your value. Count by multiples of 1, 2, 5, or 10. Step 3: each point by finding the x-value and drawing a line upward until you get to the right y-value. Step 4: Draw a curve that shows the pattern of the points. Do not just connect the dots. Creating Line Graphs Graphs are used to see the relationship between the independent and dependent variable. (Cause and Effect) To plot (x,y) coordinate pairs use Scatter Plots Remember to M graph area I variable on X X axis T U with labels S with evenly spaced increments C Continuous Smooth Curve or best fit line Direct and Inverse Relationships relationship when one variable, the other also. Slopes up. relationship when one variable increases, the other. Slopes. Averages When you make many measurements of the same thing you will notice that the values cluster around an average. To calculate an average, up all the measurements and by the total of measurements. Some measurements are more than the average and some are less. (if not, there is an error in your calculations) Hot Hand Average Data: 36.02, 35.41, Average = =

5 Math Memory Aids Axes: is across, is up high Order of Operations Please Excuse My Dear Aunt Sally Parentheses, Exponents, Multiplication, Division, Addition, Subtraction Metric Prefixes King Henry Died (by) Drinking Chocolate Milk I E E E E I L C C C N L O T A I T L A I I Mass and Atomic Theory of Matter Mass is measured in (kg). One gram (g) is 1/1000th of a. Mass is measured with a An is a substance that cannot be broken down into other elements. A single is the smallest amount of any you can have. Atoms of different have different masses Solids, Liquids & Gases are always. When the is, each atom has very energy of. When the is, each atom has a energy of SOLID LIQUID GAS Temperature a measurement of hot or cold that depends on the thermal energy in a material. an instrument used to measure temperaturee Fahrenheit temperature scale in which water at º and at º Celsius temperature scale in which water at º and at º. Body Temperaturee F 37 C Specific heat a property of a substance thatt tells us how much heat is neededd to raise the temperature of one kilogram of a material by one C

6 4.1 Density - per unit. Density describes how much is in a given of a material. (how much is in a given ) Units of Density are typically expressed in units of grams per milliliter ( ), grams per cubic centimeter ( ), or kilograms per cubic meter ( ) The units used for density depend on whether the substance is a solid or liquid. For use units of grams per milliliter ( ) For use density in units of or kg/m 3. Density is a Property of Matter Density changes for different substances because: Atoms may be packed or. Atoms have different 4.1 Density a Property of Matter Density is a characteristic property of material. It does change with the of a substance or its shape. Density can be used for Density for a given substance stays the at a given temperature and pressure 4.1 Comparing Density Objects will if d object > d liquid if d object < d liquid The chess piece and ball are dense than water (liquid) and.the toy soldier and crown are dense than the water (liquid) and Comparing liquids of different densities. Liquids of different densities will layer with the density liquid on the. 4.1 Comparing Density Liquids tend to be dense than solids of the same material. Water is an exception to this rule. The density of water, or ice, is than the density of water. Density water = 1 g/ml Density ice = 0.92 g/ml

7 4.1 Volume of Solids and Liquids Volume is the amount of an object takes up. π= 3.14 When calculating volume, all of the of length in the calculation must be the. Ex. l=3 cm w= 2 cm h=5 cm V=30 cm 3 Volume of a liquid Pour the liquid into a graduated cylinder and read the volume Place on a surface Read at Read at the horizontal center of the 4.1 Volume of Gases and Irregular Solids Volume of a gas Gas expands to fill its so Volume of a = Volume of its Volume of an irregular shaped object You can find the volume of an shape using a technique called. Displacement method: Put the object in water and measure the amount of water pushed aside,. V irregular solid = V displaced liquid = V with object V without object = 53 ml 50 ml = 3 ml = 3 cm 3* Note: 1 = Calculating Density To find the density of a material, you need to know the and of the material. m D V 4.1 Calculating Density from a Graph The of a substance can be determined by finding the of a vs. graph. m = V = Example: What is the density of a ball with a mass of 40 g and a volume of 10 cm 3? D = m = 40 g = 4 g/cm 3 V 10 cm 3 What is the volume of a rock that has a density of 6 g/cm 3 and a mass of 12g? V = m = g = cm 3 D g/cm 3 D = m = rise = 40 g = 4 g/cm 3 V run 10 cm 3

8 5.1 Liquids and Gases - A form of matter that flows when any force is applied, no matter how small and are both called fluids. Liquid - Phase of matter that can and change shape but has constant volume. Molecules can over and around each other. Gas - Phase of matter with molecules that can expand to fill a container. Molecules are to move around so they like liquids. Molecules in a gas have more than molecules in a liquid 5.1 Plasma A form of matter in which atoms are broken apart into separate and particles. Plasmas conduct and respond to fields. Plasmas are formed in lightning and stars. 5.1 Pressure Pressure a distributed force per unit area that acts within a fluid. A applied to a fluid creates pressure. Pressure acts in all, not just the direction of the applied force Pressure comes from between. 5.1 Intermolecular Forces forces forces between separate atoms and molecules that are at a distance but repulsive at close range. The phases of matter exist because of competition between and intermolecular forces Thermal Energy enables molecules to move from each other. Intermolecular forces make molecules move each other. Phase Thermal Energy Intermolecular forces Molecules Gas Liquid Slide over each other Solid Fixed in place 5.1 Melting and Boiling Melting point temperature at which a substance changes from a Boiling point temperature at which a substance changes from a Melting and boiling points are properties. The of a substance stays during a.

9 5.1 Evaporation and Condensation change from liquid to gas at a temperature the boiling point. Evaporation takes energy away from a liquid because the molecules that escape are the ones with the most energy. change from gas to liquid at a temperature below the boiling point. Sweat evaporating from skin removes energy and cools the body. Dew forms when water vapor in air condenses into droplets. 5.1 Convection the transfer of through the of fluids such as air and water. Fluids when they heat up. Their volume and their density. The less dense fluid then rises. When air is, it means evaporation and condensation are exactly balanced. (when one molecule evaporates, another molecule condenses). Relative humidity tells how close the air is to. Earth s is created by gigantic convection currents in the atmosphere. The Atmosphere of Earth Air is the most importantt of gases to living things on the Earth. All the oxygen our bodies need and all the needed by plants comes from air. Molecular nitrogen (N 2 ) and oxygen (O 2 ) together account for 97.2 percent of the mass of air. Argon and water vapor make up most of the rest. Gravity creates pressure because fluids have mass and weight. The Earth s atmosphere has pressure due to the of air. 5.1 Gas Laws Boyle's Law : For a fixed amount of gas at a constant temperature the volume as the pressure. ( proportional) Charles Law: For a fixed amount of gas at a constant pressure the volume as its temperature ( proportional) HIGH TEMPERATURE LOW TEMPERATURE Volume 30 Temperature

10 5.2 Solid Matter Solid-a phase of matter with a and constant volume. Molecules spring back and forth around the same average position. Crystalline Solids have an orderly, pattern of molecules or atoms. (salts, minerals, metal). Solids do have a repeating pattern of molecules or atoms. (plastic, a type of polymer). material in which individual molecules are made of long chains of repeating units. Ethylene Polyethylene (a polymer) Polymers have melting points above room temp. but lower than most metals, can be easily formed using molds, have good strength and elasticity 5.2 Physical Properties of Solids : mass per-unit volume. : tendency to crack; break ability to be pounded into thin sheets. : ability to maintain shape under the application of forces. : ability to be stretched or compressed and then return to original size. Ductility: ability to bend without breaking, or to be pulled into wires conductivity: ability to transmit heat energy. conductivity:ability to allow electricity to flow. 5.2 Heat Conduction in solids : transfer of heat by the direct contact of particles of matter. occurs between two materials at temperatures when they are touching each other. -a condition where temperatures are the same and no heat flows. Materials that conduct heat easily are called thermal and those that conduct heat poorly are called thermal. Comparing States of Matter Solid Liquid Gas/Plasma Fixed volume Fixed shape Fixed volume Shape of container Shape &volume of container Not easily compressible Not easily compressible Compressible Particles locked into Particles move, slide Particles zip past place, vibrate past each other each other Comparing Changes of State Change of State Direction Solid to liquid Liquid to solid Liquid to gas Gas to liquid Solid to gas Gas to solid Energy absorbs releases absorbs releases absorbs releases Occurs at Melting point Freezing point Boiling point Condensation point Sublimation point