Convert 2.80 x 1023 molecules of F2 to moles. (Molar Mass = 38.00 g/mole) A: 1.69 x 1047 mol F2
B: 4.56 mol F2
C:0.465 mol F2
D:2.15 mol F2
(please help)

Which is an example of the practical pursuit of alchemy? a. forming perfect substances. b. transforming base metals. c. developing metalworking techniques. d. linking spiritual characteristics with material substances.

How many protons, electrons, and neutrons are in each of the following isotopes? a. zirconium-90 b. palladium-108 c. bromine-81 d. antimony-123

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)