How many molecules are in 2.50 moles of H2O? 0 1.51 X 1024 molecules of H20
0 4.15 X 10-24 molecules of H20
0 3.01 X 1024 molecules of H20
O 8.31 X 10-24 molecules of H20

The following reaction shows sodium carbonate reacting with calcium hydroxide. na2co3 + ca(oh)2 → naoh + caco3 how many grams of naoh are produced from 20.0 grams of na2co3? (molar mass of na = 22.989 g/mol, c = 12.01 g/mol, o = 15.999 g/mol, ca = 40.078 g/mol, h = 1.008 g/mol) 12.2 grams 15.1 grams 24.4 grams 30.2 grams

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

Which of the following is a physical change? a.burning a piece of wood b.sawing a piece of wood in half c.rust forming on an iron fence d.a copper roof changing color from orange to green