Remember that:
number of moles = mass/molar mass
First, we get the molar mass of the nitrogen gas molecule:
It is known the the nitrogen gas is composed of two nitrogen atoms, each with molar mass 14 gm (from the periodic table)
Therefore, molar mass of nitrogen gas = 14 x 2 = 28 gm
Second we calculate the mass of the precipitate:
we have number of moles = 0.03 moles (given)
and molar mass = 28 gm (calculated)
Using the equation mentioned before,
mass = number of moles x molar mass = 0.03 x 28 = 0.84 gm
Atomic mass W = 183.84 u.m.a
1 mole --------- 183.84
1.4 moles ---- ?
1.4 x 183.84 / 1 = 257.376 g
hope this helps!
We would use miles to measure the diameter of the earth because that is the greatest measure of length that is possible to measure something large.
The Law of Conservation of Energy states that, within a closed system, the total amount of energy remains constant. However, energy may change from kinetic to potential and vice versa. The total energy will not have changed. <span>Enthalpy is a measure of the amount of energy that exists in a system at constant pressure. </span>