Chemistry Day 7 Friday, September 7 th Monday, September 10 th, 2018
Do-Now Title: Ch. 13/14 Notes C 1. Write down today s FLT 2. List the three states of matter and list an example for each 3. List two similarities between gases and liquids 4. is the change of a liquid into a vapor 5. Explain why changing the temperature can help speed up the process of evaporation. 6. We will take notes under our do-now. Draw or fold your column for cornell notes. Finished? Take out your planner and table of contents.
FLT I will be able to identify the temperature and pressure conditions for states of matter by completing Ch. 13/14 Notes C Standard HS-PS1-4: Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.
Notes Protocol Title your notes & add assignment # Complete Cornell-style Copy down all bolded ideas Noise level 0 Raise hand to question/comment Be prepared to pair-share-respond
Changes of State
Changes of State: Draw This Sublimation Melting Vaporization Freezing Condensation KE Increases
Changes of State Sublimation = Direct change from solid to vapor (without passing through liquid phase)
Changes of State Sublimation can occur because solids and liquids have vapor pressure Sublimation occurs in solids with vapor pressures that exceed atmospheric pressure at or near room temperature.
Sublimation Applications: Freeze-dried goods, coolants, and air fresheners.
Phase Diagrams Phase Diagram = Diagram that shows the relationships among solid, liquid, and vapor states of a substance
Phase Diagrams Shows the temperature and pressure at which substances exist at each state You can locate the normal melting point, normal boiling point, triple point, and critical point on the diagram
Triple Point
Phase Diagrams Triple Point = Set of conditions at which the three phases exist in equilibrium At the critical point, the physical properties of the liquid and gaseous states are identical
That s it J
States of Matter Inquiry Mini- Lab
Problem Through a variety of different procedures, determine whether the unknown substance and water solution that the beaker contains is a solid or a liquid.
Chemistry Day 8 Tuesday, September 11 th Wednesday, September 12 th, 2018
Do-Now Title: Inquiry Demo 1. Write down today s FLT 2. What do you think atoms are? 3. What do you think atoms are made of? 4. Draw what you think an atom looks like. Label your drawing. 5. What tools do you think you would need in order to discover or study atoms? 6. Underneath your do-now, write Demonstration Notes 7. Turn in your lab worksheet to the HW box Finished? Take out your planner and table of contents.
Demo There will be a sponge, rubbing alcohol, dry ice, and a sealed glass jar Underneath your do-now, write a prediction about what you THINK will happen Use your pro-talk sentence frame In my opinion because to make a prediction about what you THINK will happen.
Demonstration We already predicted what we will see Observation expectations: Watch with your eyes Wait until the demonstration is finished to write or say anything Summarize in 1-2 sentences OR a simple diagram
Demo Now, write down three questions you have about what you saw or about the experimental variables. Questions should be science-related and something you cannot yet answer
Demonstration Partner(s): Share each of your questions with each other Decide as a group which question is the best and could be answered with additional evidence, and everyone should write it on their paper. If it is your own question, simply put a star next to it
Explanation Now, we will rewatch the video with the explanation. Remember this is a preview into what we are learning. We will go over these concepts again. Write down 2-3 pieces of evidence that could use to help explain the experiment or your question.
Conclude Use your evidence to try to answer your question. You may need to make an inference. Use one of the following pro-talk sentence frames: If we look at both. and. We can see that. Based on the evidence, such as, we can conclude that.
FLT I will be able to describe early ideas about the atom by completing Early Atomic Theory Notes A Standard HS-PS1-8: Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay
Early Atomic Theory: Part A
Defining the Atom
What is an Atom?
What is an Atom? Atom = the smallest particle of an element that retains its identity in a chemical reaction An atom is extremely small - what would be needed in order for people to discover it?
A history of the atom Ancient Greece: Philosopher Democritus did not discover the atom, but he was one of the first to suggest their existence.
A history of the atom Democritus described atoms as indivisible and indestructible. Was he correct? Could he support his ideas? à There was no evidence to support Democritus ideas (yet)
John Dalton - 1776-1844 John Dalton was a chemist who studied gases, pressure, and the existence of atoms.
John Dalton - 1776-1844 John Dalton = supported Democritus idea with scientific evidence. Came up with the early ideas for atomic theory...
Dalton s Atomic Theory 1. All elements are composed of tiny indivisible particles called atoms
Dalton s Atomic Theory 2. Atoms of the same element are identical. The atoms of any one element are different from those of any other element.
Dalton s Atomic Theory 3. Atoms of different elements can mix or combine in simple whole-number ratios to form compounds
Dalton s Atomic Theory 4. Chemical reactions occur when atoms are separated, joined, or rearranged. Atoms of one element, however, are never changed into atoms of another element as a result of a chemical reaction.
Note: Dalton s Atomic Theory Not all of Dalton s ideas were correct...as we will see when we talk about modern atomic theory :)
How Can We Study Atoms? Atoms can be seen using extremely high powered microscopes, such as scanning tunneling microscopes.
Pair-Share-Respond 1. What is an atom? 2. What did Democritus believe? 3. List the four parts of Dalton s atomic theory.
Chemistry Day 9 Thursday, September 13 th - Friday, September 14 th
Do-Now Title: BrainPOP: Atoms 1. Use your periodic table to complete the donow (questions 1-10) on the worksheet provided. Do not turn over until instructed to do so. Finished? Take out your planner and table of contents.
FLT I will be able to describe early atomic models by completing Early Atomic Theory Notes B Standard HS-PS1-8: Develop models to illustrate the changes in the composition of the nucleus of the atom and the energy released during the processes of fission, fusion, and radioactive decay
Structure of the Atom
What is an atom made of? As it turns out, atoms ARE divisible, as three main subatomic particles were discovered: Protons Abbreviation: p + Neutrons Abbreviation: n 0 Electrons Abbreviation: e -
Protons = Subatomic Particles Charge: +1 charge Location: particles found in the nucleus of an atom Mass: Relative mass = 1
Neutrons = Subatomic Particles Charge: uncharged Location: particles found in the nucleus of an atom Mass: Relative mass = 1
Electrons = Subatomic Particles Charge: -1 charge Location: particles found orbiting around the nucleus Mass: Insignificant mass
How???? If atoms were so difficult to discover given their tiny size, how were subatomic particles discovered??
What does this mean? What do we know about the two ends of magnets? What happens when we push magnets close together (two different things can happen)? Why?
The discovery of the electron... In 1897, J.J. Thomson discovered the electron He conducted experiments using electric currents passing through gases at low pressure
The discovery of the electron... These electric currents produced a cathode ray (a glowing beam) that traveled from the cathode (-) to the anode (+)
What does this look like?
In summary Because the movement of the stream was from the cathode (negative end) to the anode (positive end), there must be some part of the atom that is NEGATIVELY charged
Protons & Neutrons 1886: Goldstein performed a similar experiment and observed that there were positively-charged particles traveling toward the cathode. These positive particles would later be called protons.
Protons & Neutrons 1932: Chadwick discovered the neutron. This particle was hard to discover because it is neutral, but it has a significant mass (about equal to a proton) that Chadwick studied.
Our Particles
Okay, so there are three particles... How did scientists figure out the atom s composition?
Developing Atomic Theory Dalton thought atoms were simply indivisible spheres plum pudding model: J. J. Thomson thought there were just (-)-charged particles scattered within a (+)-charged sphere But then someone else discovered the nucleus...
Ernest Rutherford In 1911, Rutherford s experiments involved shooting a beam of POSITIVELY CHARGED alpha particles at a thin sheet of gold foil He noticed that the vast majority of alpha particles passed through the foil easily. However, there were a FEW particles that were DEFLECTED back (did not go through). The ones that hit dead center were completely reflected
Rutherford s Conclusions Most of the particles passed through --> Most of an atom is empty space A few (very few) particles were deflected back --> since the alpha particles are positive, there must be a tiny, dense, positivelycharged center in an atom
Our atomic model so far... Atoms are composed of three main subatomic particles: p +, n 0, e - Protons and neutrons are located in the nucleus of the atom, which is a very small, but dense (contains a LOT of mass in a small volume) Electrons are VERY tiny, negatively charged, and orbit around the nucleus. They make up most of the VOLUME of the atom. Electrons determine the properties of our atoms
But of course......we still haven t talked about modern atomic theory and models yet :)
CW 1. Ch. 4 Review Questions Complete on a separate paper Pg. 105: Questions and Problems #9, 11-13, 15-17, 19, 21-28 2. Stamps or study Ch. 4