To determine the mass in grams of any element, you would a-divide the mass of a mole of the element by molar mass
b-subtract the mass of a mole of the element from Avogadro’s number
c-add the mass of a mole of the element to Avogadro’s number
d-multiply the mass of a mole by its molar mass

d-multiply the mass of a mole by its molar mass

Explanation:

Mass of an element, Z, which is measured in grams is related to the number of moles contained in that element and its molar mass, which can be expressed using the formula:

number of moles (n) = mass ÷ molar mass

This means that the mass (in grams) can be calculated by multiplying the number of moles in the element by its molar/atomic mass. That is;

Mass (g) = number of moles (n) × molar mass (MM)

calculate how many grams of ammonia can be produced from 4.21 grams of

n2 + 3h2 = 2nh3

my answer:

25.0g n2 x (1 mol/ 28.0gn2) x (2 mol nh3/ 1 mol n2) x (17.0g nh3/ 1 molnh3) = 30.36g n2

25.0g h2 x (1 mol h2/ 2.00g h2) x (2 mol nh3/ 3 mol h2) x (17.0g nh3/ 1 mol nh3) = 141.67g h2

lr = n2