science equation question?

Question

i'm not very good at math at all, and i'm not good at science. i can't find how to do this in my book, so can someone please tell me how to do this? Thanks to those that answer! i really appreciate it. :)

"Hydrogen and oxygen react chemically to form water. how much water would be formed if 4.8 grams of hydrogen reacted with 38.4 grams of oxygen?"

Answer 1

The math is not all that hard and neither is the science. What you need to know is that you must work with MOLES OR G-ATOMS with these type problems. The rest is conversions to and from mass. The reaction is:
2H2 + O2 -> 2H2O.
To find g-atoms: for H2, g-atomsH2=4.8/2
for O2, g-atomsO2=38.3/32
The reaction tells us that for each g-atom of O2 that is involved, 2 g-atoms of H2 are involved. Scaling up, the 2.4 g-atoms H2 require 1.2 g-atoms O2. This is about the amount of O2 available. From the reaction, we form 2.4 g-moles of water. To convert to mass, multiply by the mole wt of water (18).