Moles to grams for sodium nitrite is a multiplication by 68.994769 g/mol. A mole weighs 68.99477 g, 100 mmol weighs 6.89948 g, 10 mmol weighs 0.689948 g and a millimole is 68.9948 mg. Those four figures cover most of what gets weighed out in practice, and the table below extends them from a micromole up to ten moles.
The figure comes from the formula. Sodium nitrite is 22.9898 (Na) + 14.007 (N) + 2 × 15.999 (O), which is 68.994769 g/mol, taking standard atomic weights, and every page here computes that sum rather than quoting it. Oxygen makes up the largest share of the mass: 2 of the 4 atoms in a formula unit are oxygen, and they account for 31.998 g of the 68.99477 g, or 46.38% by mass. The derivation table below breaks the whole molecule down element by element.
Two habits make the weighed mass match the calculation. Weigh into a container you have tared rather than onto paper, because what stays behind on paper is a real loss — on a 100 mg weighing it is easily a percent. And when the target is under about 20 mg, weigh ten times that and dilute, since the absolute error of the balance does not shrink with the sample.
The curing salt in bacon and ham, used at a fraction of a percent, and a corrosion inhibitor. Pink curing salt is 6.25% of it in sodium chloride. At 68.99477 g/mol it is heavier than 2 of the 34 salts covered here, and that ranking matters more than it looks: sodium chloride has a molar mass of 58.43977 g/mol, so a gram of it contains 18.1% more formula units than a gram of sodium nitrite. Weigh by mass and you are not weighing equal amounts of substance.
Two practical things move the result. Purity below 100% means the weighed mass overstates how much compound you have — at 98% assay, 1.3799 g of every 68.99477 g is not the compound — and any water picked up from the air does the same. Both are systematic, so they shift every solution made from that jar in the same direction.
The formula
n- The amount of sodium nitrite you need, in moles
68.994769- The molar mass of sodium nitrite in g/mol, derived from its formula
m- The mass to weigh out, in grams
How it works, step by step
- Enter the amount you need, in moles.
- It is multiplied by 68.994769 g/mol.
- The result is the mass to weigh out, also given in milligrams.
- Weigh into a tared container; anything left in the boat is a real loss from the amount you calculated.
Worked examples
5 mmol of sodium nitrite in grams
5 mmol × 68.99477 g/mol = 0.344974 g, which is 344.974 mg. Doubling the amount doubles the mass to 0.689948 g, because the relationship is a plain proportion once the molar mass is fixed.
250 mmol of sodium nitrite in grams
250 mmol × 68.99477 g/mol = 17.2487 g, which is 17,248.7 mg. Doubling the amount doubles the mass to 34.4974 g, because the relationship is a plain proportion once the molar mass is fixed.
2 mol of sodium nitrite in grams
2 mol × 68.99477 g/mol = 137.99 g, which is 137,990 mg. Doubling the amount doubles the mass to 275.979 g, because the relationship is a plain proportion once the molar mass is fixed.
How to read your score
Frequently asked questions
What is the molar mass of sodium nitrite (NaNO2)?
It is 68.994769 g/mol. That is the sum of the standard atomic weights of every atom in the formula: 22.9898 (Na) + 14.007 (N) + 2 × 15.999 (O). One mole of sodium nitrite therefore weighs 68.99477 g, and a gram of it is 14.494 mmol.
What percentage of sodium nitrite is oxygen?
46.38% by mass. Each formula unit contains 2 oxygen atoms contributing 31.998 g of the 68.99477 g total, so 100 g of sodium nitrite contains 46.38 g of oxygen and a kilogram contains 463.77 g of it.
How many grams is one mole of sodium nitrite?
68.994769 g, by definition of the molar mass. Two moles is 137.9895 g and half a mole is 34.49738 g.
How many grams is 0.1 mol, and how many milligrams is 1 mmol?
0.1 mol of sodium nitrite is 6.89948 g. One millimole is 68.9948 mg and one micromole is 68.9948 µg, which is the range most bench work sits in.
How do I weigh out an amount too small for my balance?
Weigh a larger mass and dilute it. To get 0.6899 mg of sodium nitrite, weigh 6.899 mg into 100 mL, then take 10 mL of that: the absolute error of the balance stays the same while the amount delivered falls by a factor of ten.
Should I use the hydrate or the anhydrous molar mass?
This page is the anhydrous form, NaNO2, at 68.994769 g/mol. If your jar is the other form the molar mass differs and so will every mass you weigh, so check the label before using the figure. Salts that are sold as hydrates weigh more per mole because the water is part of the crystal.
Moles to grams reference for sodium nitrite
| Element | Atoms | Atomic weight | Contribution (g/mol) | By mass |
|---|---|---|---|---|
| Oxygen (O) | 2 | 15.999 | 31.998 | 46.38% |
| Sodium (Na) | 1 | 22.98977 | 22.98977 | 33.32% |
| Nitrogen (N) | 1 | 14.007 | 14.007 | 20.3% |
| Total — one mole of sodium nitrite | 68.994769 | 100% |
Standard atomic weights, IUPAC 2021. The contribution column is atoms × atomic weight, and the total is the molar mass this page uses: 68.994769 g/mol.
| Wanted | Weigh (g) | Weigh (mg) | With 2% over (g) |
|---|---|---|---|
| 1 µmol | 0.000069 | 0.0689948 | 0.000070 |
| 10 µmol | 0.000689948 | 0.689948 | 0.000703747 |
| 100 µmol | 0.00689948 | 6.89948 | 0.00703747 |
| 1 mmol | 0.0689948 | 68.9948 | 0.0703747 |
| 10 mmol | 0.689948 | 689.948 | 0.703747 |
| 50 mmol | 3.44974 | 3449.74 | 3.51873 |
| 100 mmol | 6.89948 | 6899.48 | 7.03747 |
| 250 mmol | 17.2487 | 17,248.7 | 17.5937 |
| 500 mmol | 34.4974 | 34,497.4 | 35.1873 |
| 750 mmol | 51.7461 | 51,746.1 | 52.781 |
| 1 mol | 68.9948 | 68,994.8 | 70.3747 |
| 2 mol | 137.99 | 137,990 | 140.749 |
| 5 mol | 344.974 | 344,974 | 351.873 |
| 10 mol | 689.948 | 689,948 | 703.747 |
Weigh is the amount multiplied by 68.994769 g/mol. The last column carries a 2% allowance, which is what you take when some of the solid will be left in the weighing boat.
| Compound | Formula | Molar mass (g/mol) | Millimoles in 1 g |
|---|---|---|---|
| Ammonium chloride | NH4Cl | 53.489 | 18.695 |
| Sodium chloride | NaCl | 58.43977 | 17.112 |
| Sodium nitrite (this page) | NaNO2 | 68.99477 | 14.494 |
| Sodium hypochlorite | NaClO | 74.43877 | 13.434 |
| Potassium chloride | KCl | 74.5483 | 13.414 |
| Ammonium nitrate | NH4NO3 | 80.043 | 12.493 |
| Sodium bicarbonate | NaHCO3 | 84.00577 | 11.904 |
Ordered by molar mass. The last column is 1000/M, which is the number a weighed gram actually gives you.