A rock is irregular object, it is difficult to use a ruler to determine its volume. Using spring balance, you determine that the mass of a rock in air is 0.322 kg. When the rock is lowered into water, its mass is 0.212 kg. a. What is the mass of displaced water?
b. What is the volume of water displaced?
c. What is the density of the rock?

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

Darla claims that the first periodic table developed by mendeleev was not completely accurate, so it is not useful at all. harmony argues that it establish the periodic table we use today, making it more credible. who is correct and why? darla is correct, because a model that has any mistakes should be thrown out. darla is correct, because a good model would not need to change. harmony is correct, because mendeleev’s model had all of the information correct in the first version. harmony is correct, because mendeleev’s model made predictions that came true.

How many moles are in 7.2 x 10^23 carbon molecules? (*round to the nearest hundredth and include the unit "mol c" after your number) question 6 options: