A sample of ammonia reacts with oxygen as shown. 4NH3(g) 5O2(g) Right arrow. 4NO(g) 6H2O(g) What is the limiting reactant if 4. 0 g of NH3 react with 8. 0 g of oxygen? O2 because it produces only 0. 20 mol of NO. NH3 because it produces only 0. 20 mol of NO. O2 because it produces two times less NO than NH3. NH3 because it produces three times more NO than O2.

Plz choose one of the compounds from the table and explain how you know the numbers of atoms in your formula. is it possible for two different compounds to be made from the exact same two elements? why or why not? with a limited number of elements (less than 120 are known), does this mean we also have a small number of compounds or do we have a large number of compounds in this world?

Aradio signal from a gps satellite take only about 0.067 seconds to reach a gps reciever. if the speed of light is about 300,000km/s, then approximately how far away is the reciever from from the satellite?

6. using 3 – 4 sentences explain (in your own words) why water expands when it freezes? 7. using your knowledge of colligative properties explain whether sodium chloride or calcium chloride would be a more effective substance to melt the ice on a slick sidewalk. use 3 – 4 sentences in your explanation.