How many molecules does 36.0 grams of water represent?

6g h2o x (1 mole h2o / 18.0 g h2o) x (6.022x10^23 molecules / mole) = 1.20x10^24 molecules h2o 

11 g co2 x (1 mole co2 / 44.0 g co2) x (6.022x10^23 molecules / mole) = 1.51x10^23 molecules co2 

3.0 g co2 x (1 mole c / 12.0 g c) x (6.022x10^23 molecules / mole) = 1.5x10^23 atoms c 

caco3 has formula mass = 100 g/mole 
200 g caco3 x (1 mole / 100g) x (6.022x10^23 molecules / mole) = 1.20x10^24 formula units 

 
molar mass h2o = 2x1.0 + 1x16.0 = 18.0 g/mole 
molar mass f2 = 2x 19.0 = 38.0 g/mole 
molar mass cai2 = 40.1+ 2x126.9 = 294 g/mole 
molar mass pb(no3)2 = 207.2 + 2x(14.0 + 3x16.0) = 331 g/mole 

 
80.0 g h2o x (1 mole / 18.0 g) = 4.44 moles h2o 
45.0 g c6h12o6 x ( 1 mole / 180 g) = 0.25 moles c6h12o6 
22.0 g co2 x (1 mole / 44.0 g) = 0.500 moles co2 
56.0 g n2 x (1 mole / 28.0 g) = 2.00 moles n2 

 
2.0 moles lioh x (24.0 g/mole) = 48 g lioh 
5.0 moles ba(cn)2 x (189.3 g/mole) = 950 g ba(cn)2 
3.5 moles h2o x (18.0 g/mole) = 63 g h2o 
0.75 moles cuso4 x (159.6 g / mole) = 120 g cuso4 

 
2.0 moles he x (6.022x10^23 atoms / mole) = 1.2x10^24 he atoms 

3.0 moles nacl x (6.022x10^23 units nacl / mole) x (1 na+ / 1 unit) = 1.8x10^24 na+ ions 

0.25 moles ch4 x (6.022x10^23 molecules / mole) = 1.5x10^23 molecules ch4 

there are 3 atoms / 1 molecule of h2o 
1 mole x (6.022x10^23 molecules h2o / mole h2o) x (3 atoms / 1 mole h2o) = 1.8x10^24 atoms 

 
6.02x10^23 molecules h2o x (1 mole / 6.022x10^23 molecules) = 1.00 mole h2o 

3.01x10^23 molecules c2h6 x (1 mole / 6.022x10^23 molecules) = 0.500 moles c2h6 

1.2x10^24 molecules glucose x (1 mole / 6.022x10^23 molecules) = 2.0 moles glucose 

2.41x10^24 units cacl2 x (1 mole / 6.022x10^23 units) = 4.00 moles cac2 

 
1.20x10^24 molecules x (1 mole / 6.022x10^23 molecules) x (18.0 g / mole) = 36.0 g h2o 

2.41x10^24 units x (1 mole / 6.022x10^23 molecules) x (171.3 g / mole) = 342 g ba(oh)2 

1.51x10^22 atoms x (1 mole / 6.022x10^23 atoms) x (20.18 g/mole) = 0.503 g ne 

7.53x10^22 molecules x (1 mole / 6.022x10^23 molecules) x (16.04 g/mole) = 2.00 g ch4