Explanation:
Moles of N2 = 35.0g / (28g/mol) = 1.25mol
Moles of H2 = 60.0g / (2g/mol) = 30.0mol
Since 1.25mol * 3 < 30.0mol, nitrogen is limiting.
Moles of NH3 = 1.25mol * 2 = 2.50mol.
Mass of NH3 = 2.50mol * (17g/mol) = 42.5g.
30.0mol - 1.25mol * 3 = 26.25mol.
Excess mass of H2
= 26.25mol * (2g/mol) = 52.5g.
Answer:
4) 4Fe + 3O₂ → 2Fe₂O₃
Explanation:
4Fe + 3O₂ → 2Fe₂O₃
In this equation the numbers of atoms are same in both side. There are four iron and six oxygen atoms are present on left and right side of equation. That's why atoms are conserved. This equation completely followed the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Look those up it will be easier
Atomic mass of Potassium = Mass of 1 atom of Potassium = 39.1 amu
Then
Mass of 6.02 x 1023 atoms of potassium = 39.1 x 6.02 x 1023 amu
=
We already know that
1 mole = 6.02 x 1023 atoms
Also
Number of mole = mass in grams/ atomic mass
Then
Mass in gram = Number of mole x atomic mass
= (39.1 x 6.02 x 1023)/(6.02 x 1023)
= 39.1 g
The correct option among all the options that are given in the question is the third option or option "B".
