The radius of a hydrogen atom is 37 pm and its mass is 1.67 * 10-24 g. What is the density of the atom in grams per cubic centimeter? Assume the atom is a sphere with:

Volume = (4/3) (3.14) (r^3)

Calculate the vapor pressure of a solution prepared by dissolving 5 g of water in 78 g of ethanol (CH3CH2OH) at 37 C. The vapor pressures of ethanol and water at this temperature are 115 torr (ethanol) and 47 torr (water), respectively.

How can you describe the location of hafnium (Hf, atomic number 72) on the periodic table? Choose all that apply. (A) Transition metals (B) Noble gases (C) Group 6, Period 4 (D) Group 4, Period 6

A stock solution containing Mn2 + ions was prepared by dissolving 1.166 g pure manganese metal in nitric acid? and diluting to a final volume of 1.000 L. The following solutions were then prepared by dilution. For solution A, 50.

Name two unique properties of water

How many moles are in 1.1g of FeCl3

Which scientific tool is the most useful when trying to convert a known amount of grams of water to moles of water?

What is the chemical compound of nitrogen gas?

Which of the following should be done when designing an experiment for a controlled scientific investigation? A. list the procedures B. plan the variables C. list the needed materials D. all of these

Assuming the octet rule is obeyed, how many bonds and how many lone pairs will atoms of oxygen (o) and nitrogen (n) have in order to have formal charges of + 1?

Explain why animals must eat food, but plants do not have to.