January 22nd Chemistry 11

In chemistry class today we just learned about more stoichimetry we learned how to convert from mass to moles using volume at STP.

example: When 1.5g of oxygen reacts with nitrogen monoxide how many moles of nitrogen dioxide are produced?
1.5 x 1 mol O2 / 32g x 2 mol NO2/ 1 mol O2 = 0.0094mol of NO2

2)If 2g of O2 reacts with nitrogen monoxide what volume of nitrogen dioxide is present at STP?
2.0g x 1mol O2 / 32g x 2 mol NO2/ 1 mol O2 x 22.4L / 1mol NO2 = 7.8L of NO2

3) in the formation of Copper (II) oxide 3.5g of copper react. How many moles of copper oxide are produced.
3.5g x 1mol Cu/ 63.5g x 2mol CuO/ 2mol Cu = .55mol CuO