Suppose your teacher asks you to separate a mixture of sand and water. which of the following methods would you use: distillation, filtration, or evaporation? explain your answer

Imagine that you push on a large rock. at what point does your effort change the rock’s mechanical energy?

What is the typical rotational frequency frot for a molecule like n2 at room temperature (25∘c)? assume that d for this molecule is 1å=10−10m. take the total mass of an n2 molecule to be mn2=4.65×10−26kg. you will need to account for rotations around two axes (not just one) to find the correct frequency. express frot numerically in hertz, to three significant figures.

Select the statement that describe chemical properties a. antacid tablets neutralize stomach acid b. helium is the lightest monatomic element c. water freezes at 0 celsius d. mercury is liquid at room temperature