An unknown element is found to contain 45 protons and an atomic mass of 64, what is its atomic number?

Atank contains 240 liters of fluid in which 10 grams of salt is dissolved. brine containing 1 gram of salt per liter is then pumped into the tank at a rate of 6 l/min; the well-mixed solution is pumped out at the same rate. find the number a(t) of grams of salt in the tank at time t.

One of the few xenon compounds that form is cesium xenon heptafluoride (csxef7). how many moles of csxef7 can be produced from the reaction of 14.0 mol cesium fluoride with 14.0 mol xenon hexafluoride? csf(s) + xef6(s) csxef7(s)

What can a drop of liquid mercury be described as?