3. Read each description and determine whether it is a pure substance or mixture. Then further classify the matter as element, compound, homogeneous mixture, or heterogeneous mixture. Description Pure Substance or Mixture? Classification? (Element, Compound, Homogenous mixture or heterogeneous mixture)
1. Chocolate syrup is added to milk and stirred

2. Copper metal (used to make wires)

3. Sand is added to water

4. Distilled water

5. Tap water

6. Diamond

7. Table sugar

8. Sugar added to a cup of coffee and stirred

9. Kool-aid is added to water

10. Coca-cola

11. Helium gas (used to inflate a balloon)

12. Mercury metal (used in old thermometers)

13. Hydrogen gas (an explosive gas)

14. Trail mix (peanuts, pretzels and m&m's)

15. The air we breathe

Salicylic acid is a very important acid. it is used to synthesize the aspirin by treating with acetic anhydride. a 0.2015-g sample of salicylic acid was dissolved in a 100.00-ml volumetric flask, and the solution was diluted to the mark. a 10-ml aliquot of this solution was titrated with standard naoh (0.01130 + 0.2% n) to a phenolphthalein faint pink color end point at 19.81 ml. (a) (calculate the normality of the salicylic acid solution used in the titration. (b) assuming the salicylic acid is pure, what is the equivalent weight of the salicylic acid? practice problems for the final exam (continued) (c) (calculate the inherent error in the determination of the equivalent weight you calculated in part (b). use the following absolute errors in the equipment /glassware when calculating the inherent error. 5.00-ml pipet: + 0.02 ml 100-ml volumetric flask: + 0.08 ml analytical balance: + 0.2 mg 25-ml buret: + 0.03 ml

I'm learning about the periodic tables and what each subject's configuration is. for example, hydrogen is 1s^1, but i don't understand how you get that. can someone me understand how to figure out how to figure this out? sorry if the question makes no sense, but it would really a lot if you could me understand! you so much if you can!

The semi-conductors on the periodic table are classified as