Answer:
This question is incomplete. The completed question is below
Procedure
1. Read and complete a lab safety form.
2. Place about 50 copper pellets into a plastic petri dish. Place the cover on the dish, and secure it with tape.
3. Hold the dish by the edges. Gently vibrate the dish from side to side no more than 1–2 mm. Observe the pellets. Record your observations in your Science Journal.
4. Repeat step 3, vibrating the dish less than 1 cm from side to side.
5. Repeat step 3, vibrating the dish 3–4 cm from side to side.
if the pellets represent particles in matter, what do you think the shaking represents?
Explanation:
This procedure seeks to illustrate the "properties" of particles in matter. The shaking of the pellets represents the movement of the particles of matter (which occurs in liquids and gases). This is because the movement of particles in a liquid and gaseous state freely moves around (reason the petri-dish was vibrated so the pellet particles which serve as the liquid/gaseous particles can move freely).
NOTE: The particles in a solid have a highly restricted movement (or no movement) because of the compact nature of the particles within the solid.
Answer:
B.) The drug gets carried through a stationary phase by a mobile phase and the retention time identifies the drug.
Explanation:
Chromatography is used in purifying complex mixtures of organic compounds. It uses the adsorption tendencies of compounds to seperate and identify them.
Chromatography is made up of two phases in contact, the stationary phase or non-mobile phase and the mobile phase. The movement of the mobile phase over the stationary phase causes the separation of a mixture into its constituents.
The stationary phase is made up of silica-gel or alumina in a solvent (an adsorbent) and the mobile phase or carrier is the organic solvent which is the drug.
The mass number is equal to the number of protons plus the number of neutrons. From the periodic table, we can see that chromium has an atomic number of 24, which means its nucleus contains 24 protons. ... Therefore, the chromium-52 isotope contains 28 neutrons in its nucleus.
Probably A, since it’s the only covalent compound. The rest are ionic compounds.