Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
17 Cards in this Set
- Front
- Back
|
4 reasons things are soluble |
*All ammonium (NH4+) and Group 1A (Li+, Na+, K+, Rb+, Cs+) salts are soluble. *All nitrates (NO3-) and acetates (CH3COO-) are soluble. *Most chlorides (Cl-), bromides (Br-), and iodides (I-) are soluble, except Ag, Hg, and Pb. *Most sulfates (SO42-) are soluble, except Hg, Pb, Ca (slightly soluble), Sr, and Ba. |
|
|
5 reasons things are insoluble |
*Most carbonates (CO32-) are insoluble, except when combined with ammonium (NH4+) or Group 1A salts. *Most phosphates (PO43-) are insoluble, except when combined with ammonium (NH4+) or Group 1A salts. *Most oxides (O2-) are insoluble, except when combined with ammonium (NH4+) or Group 1A salts. *Most hydroxides (OH-) are insoluble, except when combined with ammonium (NH4+) or Group 1A salts or Ca, Sr, and Ba (slightly soluble). *Most sulfides (S2-) are insoluble, except when combined with ammonium (NH4+) or Group 1A salts or Ca, Sr, and Ba. |
|
|
Calorimetry |
Study of heat exchange in chemical reactions. |
|
|
Small calorie "c" vs. food calorie "C" |
small calorie "c" = the energy needed to raise the temperature of 1 gram of water by 1°C. Equal to 4.184 Joules. food calorie "C" = 1000 small calories |
|
|
Spectroscopy |
The study of the interaction of electromagnetic radiation with matter. |
|
|
Line Spectra |
Produced by excited atoms in gas phase and contain only certain frequencies.
Ex. hydrogen line spectra |
|
|
Continuous Spectra |
The emitted radiation contains all frequencies within a region of the electromagnetic spectrum.
Ex. rainbow, lightbulb |
|
|
What kind of energy transitions were observed in Experiment 2 (Spectroscopy)? |
emission and absorption |
|
|
Describe what is meant by the term "white light" and know the wavelength range (in nm) that white light covers. List the colors of the spectrum from the highest to the lowest frequency. |
White light is visible light. It covers 400-650nm. From lowest frequency to highest frequency, the colors of the spectrum are ROYGBIV. |
|
|
What is the purpose of the "discharge tube" setup in Experiment 2 (Spectroscopy)? |
To transfer energy to the gas atoms, thus exciting them to higher energy levels. Return to lower energy levels results in emitted light. |
|
|
How does changing the slit width affect the spectrum in Experiment 2 (Spectroscopy)? |
A narrower slit creates thinner, more defined lines while a wider slit creates thicker bands of color. |
|
|
How does changing the distance from the source of light to the spectroscope affect the spectrum in Experiment 2 (Spectroscopy)? |
The further away from the light source, the weaker the spectrum. |
|
|
Outline in a few sentences how you calibrated your spectroscope in Experiment 2 (Spectroscopy). |
I placed graph paper over the viewing window, then marked the positions of well-known emission lines (violet, green, yellow) there and compared our other emissions to these standards. We also wrote equations to convert from the graph position to wavelength. |
|
|
Explain the complementary nature of absorbed/observed colors. |
Certain colors are absorbed by certain objects, meaning that none of that color will be visible to the eye. The opposite wavelengths of those colors absorbed will be reflected and we see those reflected colors. |
|
|
What is the fundamental reason why a substance absorbs visible light? |
The energies of the photons/wavelengths match the natural frequencies of the objects. |
|
|
Describe the technique of colorimetry. |
A set of solutions of known concentrations of some light-absorbing substance is place in a series of containers. An unknown concentration solution is then compared with the calibration set to obtain a match and therefore determine the concentration. |
|
|
What process removes the energy from excited food dye molecules in aqueous solution? |
Entropy / increased thermal energy. Solvent molecules bumping billions of times per second against the excited food dye molecules takes the energy from excited food dye molecules. |
