The statement which correctly describe the relationship between the reactants and the yield is this: 'the theoretical yield is calculated from the amount of the limiting reactants present'. The theoretical yields is the ideal maximum amount of a product that can be produced during a chemical reaction while the limiting reactant is the reactant that determines the maximum amount of product that can be formed.
Number of neutrons = mass number - atomic number = 40 - 19 = 21 answer
2AgNO3 + Ni2+ = Ni(NO3)2 + 2Ag<span>+</span>
From the reaction,
it can be seen that AgNO3 and Ni2+ has following amount of substance
relationshep:
n(AgNO3):n(Ni)=2:1
From the relationshep we can determinate requred moles of Ni2+:
n(AgNO3)=m/M= 15.5/169.87=0.09 moles
So, n (Ni)=n(AgNO3)/2=0.045 moles
Finaly needed mass of Ni2+ is:
m(Ni2+)=nxM=0,045x58.7=2.64g
C. Distance from Earth
The observed brightness of a star (the apparent magnitude) to an absolute magnitude, you need to know the distance [d], to the star. Alternatively, if we know the distance and the apparent magnitude [m] of a star, we can calculate its absolute magnitude [d].
*paraphrased from "COSMOS.com"
Answer: 2.60 x 10^23 molecules
50.0 grams x (1 mol/115.79 grams) = 0.431816219 moles
0.431816219 mol x (6.02 x 10^23 molecules/1 mol) = 2.599533638 x 10^23 molecules (final answer is rounded)