Answer:
Percentage yield = 85.2%
Explanation:
Given data:
Mass of Mg = 21.3 g
Actual yield of MgO = 30.2 g
Percentage yield = ?
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of Mg = mass/molar mass
Number of moles of Mg = 21.3 g / 24.3 g/mol
Number of moles of Mg = 0.88 mol
Now we will compare the moles of MgO with Mg.
Mg : MgO
2 : 2
0.88 : 0.88
Mass of MgO:
Mass of MgO= moles × molar mass
Mass of MgO= 0.88 mol × 40.3g/mol
Mass of MgO = 35.46 g
Actual yield of MgO = 30.2 g
Percentage yield:
Percentage yield = Actual yield/theoretical yield × 100
Percentage yield = 30.2 g/ 35.46 g × 100
Percentage yield = 85.2%
Answer:
it's describes the velocity. since a direction was specifically given, that means it is displacement, and displacement is to velocity while distance is to speed
You have to use avagados number... so toy take your starting number and multiple by 1/avagados number which is like 6.002^23 and that will equal your number of males... avagado always associates with moles... look up that exact number though bc I cant remember it
Answer:
The number of valence electrons in an atom is reflected by its position in the periodic table of the elements (see the periodic table in the Figure below). Across each row, or period, of the periodic table, the number of valence electrons in groups 1–2 and 13–18 increases by one from one element to the next
Answer:
See explanation
Explanation:
Let us recall that the basic rule in writing balanced chemical reaction equations is that the number of atoms of each element on the right hand side of the reaction equation is the same of the number of atoms of the same element on the left hand side of the reaction equation.
The reaction of red hot iron and steam is written as follows;
3Fe + 4H2O → Fe3O4 + 4H2.
The decomposition reaction of ammonium dichromate is written as;
(NH4)2Cr2O7 → N2 + Cr2O3 + 4H2O
Reaction of aluminium, sodium hydroxide and water is as follows,
2Al + 2NaOH + 2H2O ----> 2NaAlO2 + 3H2
Reaction of potassium bicarbonate with sulphuric acid;
2KHCO3 + H2SO4 -------> K2SO4 + 2H2O + 2CO2
Reaction of zinc and sodium hydroxide is as follows;
Zn + 2NaOH→Na2ZnO2 + H2