Mole-atom conversions 1. how many moles are 1.55 x 1027 atoms of zinc (zn)? 2. how many atoms are in 25.0 moles of calcium (ca)? 3. how many atoms are in 0.35 moles of carbon (c)? 4. how many moles are 7.6 x 1024 atoms of helium? mole-mass conversions how many moles in 28.o grams of oxygen? what is the mass of 5.0 moles of iron? find the number of moles of argon in 452 g of argon. find the grams in 16.5 mol of hydrogen.

Assume that the variables x and y are inversely related. if k = 18, what is the value of y for each of the following points? be sure and record your data to be used in the following problem.

Hot air balloons float in the air because of the difference in density between cold and hot air. in this problem, you will estimate the minimum temperature the gas inside the balloon needs to be, for it to take off. to do this, use the following variables and make these assumptions: the combined weight of the pilot basket together with that of the balloon fabric and other equipment is w. the volume of the hot air inside the balloon when it is inflated is v. the absolute temperature of the hot air at the bottom of the balloon is th (where th> tc). the absolute temperature of the cold air outside the balloon is tc and its density is ďc. the balloon is open at the bottom, so that the pressure inside and outside the balloon is the same. as always, treat air as an ideal gas. use g for the magnitude of the acceleration due to gravity.

Particles vibrate in a rigid structure and do not move relative to their neighbors.