How many electrons should be shown in the lewis symbol for hydrogen?

How many moles are in 43.9 l of oxygen

How many distinct monochlorinated products, including stereoisomers, can result when the alkane below is heated in the presence of cl2? 3 4 5 6 7?

What sources of error may have contributed to the percent yield not being 100 percent? think about things that may have led to inaccurate measurements or where mass of the product could have been lost if this experiment was conducted in a physical laboratory.