Can someone me with these questions. plz

Suppose a lab group reports a ppercent yield of sand of 105. is it really possible to collect more sand than was originally represented? what is the possible explanation for the extra product?

From the options provided for each element below, choose the properties that it may have based on its location in the periodic table fluorine (f): highly reactive nonmetal shiny a conductor

Suppose you wanted to make 100 grams of water. what is the molar mass of water (h2o)?