Wavelength is the distance between two crests on a wave. A longer wavelength means the wave has less energy and lower frequency, and a shorter wavelength means the wave has a higher frequency and energy.
Waves with higher frequency and energy are shown on the left side of the diagram while lower frequency and energy waves are shown on the right side.
The energy of a photonis found using this equation. If you were to be looking for the energy in a mole, you would just have to multiply your number that you get for energy of a photon by Avogadro's number 6.02 x 10^23.
These are great videos for describing periodicity and electron configurations. Bozeman Science always makes the best study videos and I always refer to them when I am preparing for tests.
Periodicity Bozeman Science
Electron Configuration
Here are some extra study links that really helped me:
This quiz was a little easier than the others because the material was easier to comprehend. I freaked out the night before because I thought that I was not going to be ready for the quiz, but it turned out I was. There was much less math in this unit than previous ones which helped a lot with time, and many questions were about different electron configurations. I am excited for the rest of the unit because it is proving to be easier than the last units!
The Flame Test lab was so cool! We tested different solutions in a Bunsen burner to see what color light the flame emitted. Some of the colors were really cool; we had a bright emerald green and a fiery ruby red. This lab although cool, was one of the more dangerous labs in that a few students got minor burns, but it was in the name of SCIENCE.
The original color of the flame in the Bunsen burner
This lab was very similar to the titrations lab. We had to standardize a base (NaOH) then titrate a mystery acid (which turned out to be the aspirin we made earlier in the year) in order to determine its molar mass. We essentially had the same procedure as the titrations lab except we titrated the aspirin instead of the vinegar in this lab. The only problem that came up was that the mystery acid took a long time to dissolve in the water, so we spent a long time on waiting for the mystery to dissolve. Eventually, Frankenberg decided that we needed to put the acid solution on a hot plate to speed up the process, and that helped immensely.
Today's acid base test was awful. I guessed on about 5 questions and did not feel confident with half of my answers. The test itself had a lot of the same content that was on the practice resources, but some of the questions needed elevated thinking. Unlike the last quiz, I felt more confident with my definition-y answers because they were easier to process, and the math questions were all pretty long and complex. I am praying for a C.
Taking this quiz, I felt OK. I can't really say I was confident because I felt so rushed the entire time since I had less time to finish the quiz than normal, but getting my grade back later that week, I felt like it reflected accurately my comprehension of the unit. It was not a good grade, to say the least, but it was only a quiz thankfully and now I have worked toward correcting these mistakes. I thought, going into the quiz, that I would be most tripped up by the ICE box and math problems, but I found that I was actually tripped up by the definition-y problems which makes sense since I didn't study that part of the material as much. I'm glad we've been doing long labs and low-stress activities in class because I have been able to go home and study for the test this Thursday. I'm glad that I've made these mistakes and am able to correct them, but I just have to pray that I don't make these silly mistakes on the test!
The titration lab consisted of finding the amount of NaOH that could be added to solutions of vinegar and KHP in order to determine the molarity of the NaOH and acetic acid. It was very cool to see the sudden color change from completely clear to pink when the equilibrium point was reached, but we had to be very careful when reaching that point because one drop over could result in inaccuracies in our calculations. This lab, although a little difficult to master at first, was one of the more enjoyable labs we have done all year.
Basic Info:
Acids- feel sticky, taste sour, change litmus red, corrosive to metals, have a pH of 0-6.9
Bases- feel slippery, taste bitter, change litmus blue, have a pH of 7.1-14
Types:
There are two types of acids and bases that we are studying this unit: Arrhenius, and Bronsted-Lowry.
Arrhenius- Arrhenius acids form hydrogen ions in aqueous solution and Arrhenius bases form hydroxide ions (we learned about these a little in the Chemical Reactions unit)
Arrhenius Video
Bronsted-Lowry- acid is defined as anything that releases H1+ ions; a base is defined as anything that accepts H1+ ions (this is new to this unit)
Bronsted-Lowry acids and bases have conjugate acid and base pairs where the proton donors and acceptors are paired together
The CH3COOH is the proton donor and the CH3COO- is the proton acceptor
Bronsted-Lowry Video
Acidic and Basic:
We can determine if a solution is acidic or basic by knowing its concentration of [H+] and [OH-]
[H+]>[OH-] shows that the solution is acidic
[H+]<[OH-] shows that the solution is basic
Temperature does not affect [H+] or [OH-]
Water can act as both acid or base so it is called amphoteric
Calculating pH, pOH, [H+] and [OH-]
There are a few formulas that help with calculating these values.
If you are given the pH of a solution and you are trying to find the [H+] use the formula 10^-pH
If you are given the [H+] and are trying to find the pH use the formula -log[H+]
If you are given the pH and are trying to find the pOH use formula 14-pH
If you are given the [H+] and are trying to get to [OH-] use the formula (1x10^-14)/[H+]
The rest of the calculations (like the inverses) are shown here in this cool flow chart.
