1.14k likes | 1.25k Views
C.F. 1 MOLE : Molar Mass in Grams. Question gives you moles and asks for number of atoms Question gives you number of atoms and ask for moles. Question gives you moles and asks for grams Question gives you grams and asks for moles. C.F. 1 MOLE : 6.02 x 10 23 ATOMS.
E N D
C.F. 1 MOLE : Molar Mass in Grams Question gives you moles and asks for number of atoms Question gives you number of atoms and ask for moles Question gives you moles and asks for grams Question gives you grams and asks for moles C.F. 1 MOLE : 6.02 x 1023 ATOMS
C.F.Molar Mass = MOLE = 6.02 x 1023 atoms Question gives you grams and asks for number of atoms • Convert grams to Moles • Convert moles to # of atoms C.F.6.02 x 1023 atoms = MOLE = Molar Mass Question gives you number of atoms and asks for mass in grams • Convert # of atoms to moles • Convert moles to grams
INSTRUCTIONS • Draw sideways T • Write your “given” in the first box • If you are given GRAMS: • Use Periodic Table to find molar mass of element. • Solve • If you are given # OF ATOMS • Use “6.02x 1023 atoms” • Solve
INSTRUCTIONS • Draw sideways T • Write your “given” in the first box • If you are given GRAMS: • Write “1 mole” in the next top box. • Then write the molar mass in the opposite corner. • Solve for mole. • Convert mole to number of atoms by: • Write “6.02 x 1023 atoms” in the next top box • Then write “1 mole” in the opposite corner • Solve
INSTRUCTIONS • Draw sideways T • Write your “given” in the first box • If you are given GRAMS: • Find molar mass using periodic table and write in the opposite corner. • Write “1 mole” in the box above. • Convert mole to number of atoms by: • Then write “1 mole” in the opposite corner • Write “6.02 x 1023 atoms” in the box above • Solve • If you are given # OF ATOMS • Then write “6.02x 1023 atoms” in the opposite corner. • Write “1 mole” in the box above. • Convert mole to grams by: • Then write “1 mole” in the opposite corner. • Find molar mass using periodic table and write it in the box above • Solve
1. Quantum Model of the Atom OBJECTIVE: To understand energy, and how we got to our present understanding of an atom
1. Quantum Model Wavelength: distance between two points, either crests or troughs
1. Quantum Model Frequency: number of waves that passes a certain point in 1 second.
1. Quantum Model 2 properties of waves Wavelength: distance between two points, either crests or troughs Symbol: l Units = meters, m Frequency: How many waves that passes a certain point in 1 second. Symbol: v Units = Hz, or sec-1 INVERSE relationship between wavelength and frequency
1. Quantum Model 2 properties of waves Wavelength: is… Symbol: ? Units = ? Frequency: is… Symbol: ? Units = ? What does it mean for wavelength and frequency to have an inverse relationship?
1. Quantum Model Calculations using lv = c A wave has a frequency of 4.61 x 104 Hz. What is its wavelength in meters? Write the equation: lv = c Plug in values. C = 3.0 x 108 m/s ALWAYS Rearrange equation to solve for unknown. Solve
1. Quantum Model Calculations using lv = c Your favorite radio station broadcasts the signal at 99.5 MHz. This is equal to 9.96 x 107 Hz. Calculate the wavelength in meters. Write the equation: lv = c Plug in values. C = 3.0 x 108 m/s ALWAYS Rearrange equation to solve for unknown. Solve
1. Quantum Model Calculations using lv = c Photosynthesis uses light waves with a wavelength of 660 nm to convert CO2 and H2O into glucose and O2. 660 nm = 6.6 x 10-7m Calculate the frequency. Write the equation: lv = c Plug in values. C = 3.0 x 108 m/s ALWAYS Rearrange equation to solve for unknown. Solve
1. Quantum Model Answer on Warmup Paper. Label it as “WAVES” Your favorite FM radio station broadcasts at a frequency of 101.1 MHz. This is equal to 1.011 x 108 Hz. What is the wavelength of this station in meters? A police officer is using a radar gun for speeding citations. The gun uses waves with a wavelength of 8.45 nanometers. This is equal to 8.45 x 10-9 meters. What is the frequency in Hz?
1. Quantum Model Calculations using lv = c Photosynthesis uses light waves with a wavelength of 660 nm to convert CO2 and H2O into glucose and O2. 1 nm = 1.0 x 10-9m. Calculate the frequency. Convert 660nm to meters using sideways-T Write the equation: lv = c Plug in values. C = 3.0 x 108 m/s ALWAYS Rearrange equation to solve for unknown. Solve
Make sure that l is in METERS, or that v is in Hz If not, then convert to METERS or Hz using the conversion factors given to you. Solve: Step-by-step instructions on how to solve should be in your notes Does your final answer have the units that is asked for in the problem?
1. Quantum Model X-Ray Sunburn from UV rays
1. Quantum Model Heat energy in the form of Infrared waves
1. Quantum Model In the 1900’s physicist thought they were able to explain any type of phenomena. They organized the world into two categories: Matter Energy - Made up of particles - Energy, in the form of light, existed as waves
1. Quantum Model • In the 1900’s physicist thought they were able to explain any type of phenomena. • They organized the world into two categories: • Matter Energy • Made up of particles -Energy, in the • - Has mass and volume form of light, existed as waves • - does NOT have mass or volume
1. Quantum Model Energy as massless waves
1. Quantum Model Relationship between ENERGY and WAVELENGTH
1. Quantum Model Max Plank Quantized? Means that energy is gained or lost ONLY in amounts of WHOLE NUMBERS Means that energy is transferred in “packages” called a QUANTUM = the smallest unit of energy Similar Examples: Musical instruments are “quantized” in that they can only produce certain notes, like C or F#. US Dollars is “quantized” in whole number multiples of pennies.
1. Quantum Model What does it mean for energy to be QUANTIZED? What is a quantum? How is a penny like a quantum?
1. Quantum Model Max Plank E = hv
1. Quantum Model Einstein and the Photoelectric Effect Photoelectric Effect: when electrons are released from a surface of a metal that has been exposed to light
1. Quantum Model Einstein and the Photoelectric Effect Why does nothing happen when red light makes contact with the metal? Why does only violet light release an electron?
1. Quantum Model Einstein and the Photoelectric Effect It was thought that color should not matter, only intensity But experiment showed that color does matter.
1. Quantum Model Einstein and the Photoelectric Effect Einstein applied Plank’s idea, that…, to the photoelectric effect…
1. Quantum Model Einstein and the Photoelectric Effect Light is also quantized Light is a stream of particles called PHOTONS PHOTON: a particle of light
1. Quantum Model Why Plank and Einstein are important
1. Quantum Model Why Plank and Einstein are important Plank’s and Einstein's postulate that energy is quantized is in many ways similar to Dalton’s description of atoms. Both theories are based on the existence of simple building blocks, atoms in one case, and quanta in the other. The work of Plank and Einstein thus suggested a connection between the quantized nature of energy and the properties of individual atoms. In fact, Einstein's Nobel Prize was awarded for his work in the photoelectric effect and demonstrating its fundamental important, not for his famous E=mc2 equation.
1. Quantum Model Summary of Plank and Einstien Energy is quantized. It can only occur in discrete units called quanta. Light, in fact the entire electromagnetic spectrum, exists as BOTH waves and particles. Interesting Implications – What their findings mean Energy has “mass!” If it has mass, then energy is a form of matter! If energy, in the form of light, is both wave and particle, then ALL MATTER exists as both waves and particles
1. Quantum Model • In the 1900’s physicist organized the world into two categories: • Matter Energy • Made up of particles -Energy, in the • - Has mass and volume form of light, existed as waves • - does NOT have mass or volume • But after Plank and Einstein’s work, we now see that ENERGY (light) and MATTER NOT separate, but related
1. Quantum Model What does it mean for light to be quantized? What is a photon? What is a quantum? How is a photon like a quantum?
1. Quantum Model How is a penny or steps on a stair like a quantum of energy?
1. Quantum Model Plank + Einstein = Calculating the Energy of one Photon E = (hc)/l
1. Quantum Model Plank + Einstein = Calculating the Energy of one Photon E = (hc)/l h = Plank’s Constant h = 6.626 x 10-34J•sec This number NEVER changes (J = Joule, the unit for measuring energy)
1. Quantum Model Plank + Einstein = Calculating the Energy of a Photon E = (hc)/l The blue color in fireworks results when copper is heated to about 1200°C. The blue light has a wavelength of 450 nm. What is the unit of energy emitted? Write equation Plug in values. h = 6.626 x 10-34J•sec ALWAYS Solve ANSWER = 4.42 x 10-19 J
1. Quantum Model Plank + Einstein = Calculating the Energy of a Photon E = (hc)/l A ruby laser used at grocery stores to scan barcodes emits a red light at a wavelength of 694.3 nm. What is the energy in J? 1 nm = 1.0 x 10-9 m Write equation Make sure l is in METERS. Plug in values. h = 6.626 x 10-34J•sec ALWAYS Plug in values. h = 6.626 x 10-34J•sec ALWAYS Solve
1. Quantum Model Plank + Einstein = Calculating the Energy of a Photon E = (hc)/l A ruby laser emits a red light at a wavelength of 694.3 nm. What is the energy in J? Write equation Make sure l is in METERS. Plug in values. h = 6.626 x 10-34J•sec ALWAYS Plug in values. h = 6.626 x 10-34J•sec ALWAYS Solve ANSWER = 2.861 x 10-19 J
1. Quantum Model Plank + Einstein = Calculating the Energy of a Photon E = (hc)/l An x-ray generator, such as those used in hospitals, emits radiation with a wavelength of 1.544 angstrom. What is the energy of a single proton? Write equation Make sure l is in METERS. Plug in values. h = 6.626 x 10-34J•sec ALWAYS Plug in values. h = 6.626 x 10-34J•sec ALWAYS Solve
1. Quantum Model Plank + Einstein = Calculating the Energy of a Photon E = (hc)/l Write equation Make sure l is in METERS. If not, then convert it to METERS using sideways T Plug in values h = 6.626 x 10-34J•sec ALWAYS Plug in values. c = 3.0 x 108 m/sec ALWAYS 4. Solve