How many grams are in 3.14 moles of PI₃?

Explanation:

We want to convert from moles to grams, so we must use the molar mass.

1. Molar Mass

The molar mass is the mass of 1 mole of a substance. It is the same as the atomic masses on the Periodic Table, but the units are grams per mole (g/mol) instead of atomic mass units (amu).

We are given the compound PI₃ or phosphorus triiodide. Look up the molar masses of the individual elements.

Phosphorus (P): 30.973762 g/molIodine (I): 126.9045 g/mol

Note that there is a subscript of 3 after the I in the formula. This means there are 3 moles of iodine in 1 mole of the compound PI₃. We should multiply iodine's molar mass by 3, then add phosphorus's molar mass.

I₃: 126.9045 * 3=380.7135 g/mol PI₃: 30.973762 + 380.7135 = 411.687262 g/mol 2. Convert Moles to Grams

Use the molar mass as a ratio.

We want to convert 3.14 moles to grams, so we multiply by that value.

The units of moles of PI₃ cancel.

3. Round

The original measurement of moles has 3 significant figures, so our answer must have the same. For the number we calculated, that is the tens place.

1292.698

The 2 in the ones place tells us to leave the 9.

3.14 moles of phosphorous triiodide is approximately equal to 1290 grams of phosphorus triodide.

A) the enthralling of formation for pure element in its standard state is always positivehope this : )

The correct answer is "hydrogen".