The reaction for the formation of MgO(s):
2 Mg (s) + O2(g) -à
2MgO(s) ΔH = -601.24
kJ/mol
<span>The enthalpy
information is taken from: http://webbook.nist.gov/cgi/inchi?ID=C1309484&Mask=2</span>
From the equation and with an enthalpy change of -231 kJ:
-231 kJ * 2 mol Mg * (1/-601.24 kJ/mol) = 0.76841 mol Mg
Then, with the molar mass of MgO = 40.3,
0.76841 mol Mg *(2 mol MgO/2 mol Mg)* 40.3 g/mol MgO = <span>30.967 g MgO</span>
Answer:
pv=nrt solution re solve it
Answer:
how strong the gravity force of black holes ?
Answer:
% weight of nickle = 24 %
Explanation:
molar mass of Nickel Sulfamate (Ni(SO₃NH₂)₂) = 250.87 g/mol
Solution
1st we write down the molar mass of Ni
molar mass of Ni = 59 g/mol
now we write down the number of moles of Ni in (Ni(SO₃NH₂)₂)
number of moles of Ni = 1 mol
Now we calculate the mass of nickle present in (Ni(SO₃NH₂)₂)
<em> mass = moles × molar mass</em>
mass = 1 mol × 59 g/mol
mass = 59 g
now we calculate the % weight of nickle in (Ni(SO₃NH₂)₂)
<em> % weight = (weight of element ÷ total weight) × 100</em>
% weight of nickle = (59 ÷ 250.87) × 100
% weight of nickle = 0.24 × 100
% weight of nickle = 24 %
What mass of the following chemicals is needed to make the solutions indicated?
Answer:
271.6g
Explanation:
The mass of the chemicals need to make the needed solution can be derived by obtaining the number of moles first.
Given parameters:
Volume of solution = 1L
Molarity of HgCl₂ = 1M
number of moles of HgCl₂ = molarity of solution x volume
= 1 x 1
= 1 mole
From;
Mass of a substance = number of moles x molar mass;
we can find mass;
Molar mass of HgCl₂ = 200.6 + 2(35.5) = 271.6g/mol
Mass of the substance = 1 x 271.6 = 271.6g