Only when there is no product that is when a chemical reaction has not occured
Answer:
58.0 g of MgO
Explanation:
in a perfect world, 70 g, however we don't live in a perfect world
The equation of reaction
2Mg + O₂ --> 2MgO
first find which element is limiting:
35 g x 1 mol/24.3 g of Mg x 2 mol of MgO/ 2 mole of Mg = 1.44 moles of MgO
35 g x 1 mol/32g of Mg x 2 mol of MgO/ 1 mole of O₂ = 2.1875 moles of MgO
This means Mg is the limiting factor, so you will be using this moles to find grams of MgO
1.44 mols of MgO x 40.3 g of MgO/ 1 mol = 58.0 g of MgO
Answer:
1s2 2s2 2p3
Explanation:
we know that the number of electrons in an atom is equal to number of protons. So the number of electrons here is 7.
Using Moller chart, the electronic configuration is writen by the electrons first enterring into 1s then into 2s after 2p. The s orbital accomodates maximum of 2 electrons.
∴ for atomic no. 7 nitrogen atom, electronic configuration is 1s2 2s2 2p3.
Let MM(x) be the molar mass of x.
MM(Pb) : MM(PbO)
=207.21 : 223.20 = 451.4 g : x g
cross multiply and solve for x
x=223.2/207.21*451.4
= 486.23 g
Percentage yield = 365.0/486.23= 0.75067 = 75.07% (rounded to 4 sign. fig.)
