Which atmospheric layer has around 80 percent of the mass of the earths armosphere?

An atomic nucleus is composed ofa)protons.b)protons and neutrons.c)protons and electrons.d)protons, neutrons, and electrons.

Use the periodic table to classify each of the elements below. cadmium (cd): vanadium (v): xenon (xe): iodine (i): potassium (k): strontium (sr):

In the following reaction, oxygen is the excess reactant. sicl4 + o2 → sio2 + cl2 the table shows an experimental record for the above reaction. experimental record trial starting amount of sicl4 starting amount of o2 actual yield of sio2 1 120 g 240 g 38.2 g 2 75 g 50 g 25.2 g part 1: calculate the percentage yield for sio2 for trial 1. also, determine the leftover reactant for the trial. show your work. part 2: based on the percentage yield in trial 2, explain what ratio of reactants is more efficient for the given reaction.