Naturally occurring copper has two isotopes, 63cu and 65cu. what is different between atoms of these two isotopes?

Pellets of calcium chloride are spread on a sidewalk covered in water that is 36°C. Under which circumstance will the calcium chloride dissolve faster?

According to the periodic trend, which of the following is most likely to have the lowest electronegativity? F N Be Li

1) In a chemical reaction, if a color change is detected, if an odor change is detected, or if a precipitate is formed, then: A. a chemical reaction has definitely occurred B. only physical reactions have occurred C.

A sample of vinegar has a pH of 5, and a sample of rainwater has a pH of 6. Which of the following statements best describes these two substances? A. Both samples are bases, and vinegar is more basic. B.

At the same temperature, a freshwater lake frezzes but a salt water bay does not because

zinc metal can be obtained from zinc oxide zno by reacting the oxide with the element carbon the products of the reaction are Zn and CO2 what mass in grams of zinc oxide is needed to react completely with 5.00 mol of carbon

7. What is the maximum number of d orbitals in a principal energy level? 2 5 3 1

Single called organism live in a pond behind school

Which of the following would most likely contain a fossil?

Karen measures the volume of gas at 200 K and 100 kPa. To correct her measurement to standard temperature and pressure (STP), what must she do? A. make a volume correction based on a higher temperature of 273 K B.