Molecular Mass

9.18x10^24 molecules CH3OH x 1 mole/6.02x10^23 molecules x 32 g/mole = 488 g (to 3 sig figs)

The mass of NH3 mole = its molecular weight = 14 + 3 x 1 = 17

The mass of H2O mole = its molecular weight = 2 x 1 + 16 = 18

This means that one mole of NH3 weigh less than one mole of H2O

Use dimensional analysis to solve this problem. First calculate the molecular mass of CO2. This is found by (use a periodic table) adding 12.011g of C to (15.999g x2) grams of Oxygen. Once you do that, you find out that 44.009g are in 1 mole of CO2. Now, simply by looking at the equation of CO2, we can tell that 2 moles of oxygen atoms are in 1 mole of Co2 (look at the subscript for Oxygen). Now, your dimensional analysis should look like this:

254g CO2 x 1 mole CO2/44.009g CO2 x 2 mole Oxygen/1 mole CO2

The answer is 11.5 moles of Oxygen in 254g of CO2.

There are 0.003659 N2O moles. So there are o.007318 moles of N.

The pressure is approx. 2 atmospheres.

Sodium reacts with water. 0.652 NaOH moles will form.

The molecular mass of propanoic acid, also known as propionic acid, is approximately 74.08 g/mol.

The volumes doubles

Ch3ch3ch3ch2nh2ch3ch2fch3ch2ph2ch3ch2i

A sample of 3,2x10 atoms of nickel is equal to 0,53.10e-23 moles.

If the mass increases with the volume (ie if the density remains the same) then the boiling point remains constant. If the volume remains contstant with rising mass (ie greater density) then the boiling point increases.

Balanced equation: 2C8H18 + 25O2 ==> 16CO2 + 18H2O
moles of octane used: 325 g x 1 mole/114g = 2.85 moles octane
moles H2O produced: 18 moles H2O/2 moles C8H18 x 2.85 moles C8H18 = 25.65 moles H2O

The answer is 6 moles.

CH is not a molecule.

The numbers of moles in 100 kg of sodium is 4 349,76.

6,35 moles of S contain 38,24059444195.10e23 sulfur atoms.

75 grams water is equal to 4,166 moles.

7,68 grams of calcium nitride is equal to 0,052 moles.

3 L / 22.414 /mole = 0.1338 moles of the gas

2 g is 0.1338 moles, or 2/0.1338 = 14.948 g/mole is the molecular weight.

( no real gas this light...methane is closest at 16 g/mole)

The solving of mole to mole problems through stoichiometry is based in ratios. Assuming the reaction formulas are simplified and balanced the moles consumed and produced can be calculated. For example in the simple combustion reaction of ethane and oxygen of:CH4 + 2O2 = CO2 +2H20 we see a molar ratio of 1:2 between methane combusted and waters produced.

The answer is 3,424 mol sucrose.

1 mole has 6,022 140 857.10e23 atoms.
Fractions of atoms (as 5,25) doen't exist.

15 grams of nitrogen are equal to 1,071 moles.

Molecular mass = sum of all atoms masses = 1(molN/mol NH3)*14.01(g/mol N) + 3(molH/mol NH3)*1.008(g/mol H) = 17.03 g/mol NH3

The answer is 1/12,044.10e23.