<em>I</em><em> </em><em>DONT</em><em> </em><em>KNOW</em><em> </em><em>THE</em><em> </em><em>ANSWER</em><em> </em><em>OF</em><em> </em><em>NO</em><em>.</em><em>B</em>
<em>SO</em><em> </em><em>SORRY</em><em> </em><em>FOR</em><em> </em><em>THAT</em><em>!</em><em>!</em><em>!</em>
Answer :
The atomic mass is the sum of the number of protons and neutrons in the nucleus of an atom.
Explanation :
Atomic number : it is defined as the number of protons or number of electrons.
Atomic number = number of protons = number of electrons
Mass number or atomic mass : It is defined as the sum of the number of protons and the number of neutrons.
Mass number or atomic mass = Number of protons + Number of neutrons
For example :
Number of protons in carbon = 6
Number of neutrons in carbon = 6
Mass number or atomic mass = Number of protons + Number of neutrons
Mass number or atomic mass = 6 + 6
Mass number or atomic mass = 12
Thus, the atomic mass is the sum of the number of protons and neutrons in the nucleus of an atom.
<h2>b is the correct answer</h2>
according In my course I studying it all
Answer:
229%
Explanation:
The equation of the reaction is;
4Al(s) + 3O2(g) ----> 2Al2O3(s)
We must first determine the limiting reactant;
Number of moles of Al2O3 produced = mass/molar mass = 72.4g/101.96 g/mol = 0.71 moles
For Al
Number of moles reacted = mass/molar mass = 49.2g/27 g/mol = 1.8 moles
If 4 moles of Al yields 0.71 moles of Al2O3
1.8 moles of Al will yield 1.8 × 0.71/4 = 0.32 moles of Al2O3
For O2
Number of moles reacted = mass/molar mass = 42.6g/32g/mol = 1.33 moles
If 3 moles of O2 yields 0.71 moles of Al2O3
1.33 moles of O2 will yield 1.33 × 0.71/3 = 0.31 moles of Al2O3
Oxygen is the limiting reactant.
% yield = actual yield/ theoretical yield × 100/1
% yield = 0.71 moles/0.31 moles × 100
% yield = 229%