HELP How much of a 1.0 g polonium-214 sample remains after 818 microseconds? The half life of polonium-214 is 163.7 microseconds.

Imagine that you own a property that is exactly 2.2 acres large. you want to sell your property, but your realtor tells you that you cannot sell your land by the acre. in order to sell your land you need to determine the area you own in units of square meters? given that there are 1.6 kilometers in 1 mile and 640 acres in 1 square mile, what is the area of land that you own in square meters square meters?

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.

How many moles of sulfuric acid (h2so4) are needed to react completely with 6.8 moles of lithium hydroxide (lioh)? 2lioh + h2so4 → li2so4 + 2h2o a. 3.4 mol h2so4b. 6.8 mol h2so4 c. 10.2 mol h2so4 d. 13.6 mol h2so4