The mass of 1.72 mol of magnesium fluoride is 107 grams.
To determine the mass of 1.72 mol of magnesium fluoride, we first need the chemical formula of magnesium fluoride. Magnesium forms a +2 ion (Mg+2) and fluoride forms a -1 ion (F-1). Since all compounds formed from ions have to be electrically neutral, we need 2 fluoride ions and 1 magnesium ion. Therefore, the formula for magnesium fluoride is MgF2.
Now we need to determine the molar mass of the compound from the molar mass values from the periodic table. Let's use a table to calculate this molar mass.
Molar mass of MgF2
Element Molar Mass (g/mol) Quantity Total (g/mol)
Mg 24.31 1 24.31
F 19.00 2 38.00
Total molar mass of MgF2 = 24.31 g/mol + 38.00 g/mol = 62.31 g/mol
This is the mass of one mole of the substance. If we have 1.72 mols of it, we multiply 1.72 by 62.31.
1.72 mol (62.31 g/mol) = 107 grams
We rounded to 107 to keep the correct number of significant digits in our answer.
CH4 + 2O2 = CO2 + 2H2O
According to molar weights :
16 gm CH4 + 64 gm O2 = 44 gm CO2 + 36 gm H2O
Since 16 gm CH4 produce 36 gm H2O
Hence 2.5 gmCH4 produce 36×2.5/16 gm H2O
= 5.265 gm of H2O
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Related Questions (More Answers Below)
Answer:
4.214 × 10^23 molecules.
Explanation:
Number of molecules in a substance can be calculated by multiplying the number of moles in that substance by Avagadro's number, which is 6.02 × 10^23.
That is, no. of molecule = n × Avagadro constant
In this case, there are 0.7 moles of fructose. Hence;
number of molecules = 0.7 × 6.02 × 10^23
no. of molecule = 4.214 × 10^23 molecules.
- The mass percent of
Pentane in solution is 16.49%
- The mass percent of
Hexane in solution is 83.51%
<u>Explanation</u>:
- Take 1 kg basis for the vapor: 35.5 mass% pentane = 355 g pentane with 645 g hexane.
-
Convert these values to mol% using their molecular weights:
Pentane: Mp = 72.15 g/mol -> 355g/72.15 g/mol = 4.92mol
Hexane: Mh = 86.18 g/mol -> 645g/86.18 g/mol = 7.48mol
Pentane mol%: yp = 4.92/(4.92+7.48) = 39.68%
Hexane mol%: yh = 100 - 39.68 = 60.32%
Pp-vap = 425 torr = 0.555atm
Ph-vap = 151 torr = 0.199atm
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From Raoult's law we know:
Pp = xp 
Pp - vap = yp Pt (1)
Ph = xh Ph - vap = yh Pt (2)
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Since it is a binary mixture we can write xh = (1 - xp) and yh = (1 - yp), therefore (2) becomes:
(1 - xp) Ph - vap = (1 - yp) Pt (3)
-
Substituting (1) into (3) we get:
(1-xp) Ph - vap = (1 - yp) xp Pp - vap / yp (4)
xp = Ph - vap / (Pp - vap/yp - Pp - vap + Ph - vap) (5)
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Subbing in the values we find:
Pentane mol% in solution: xp = 19.08%
Hexane mol% in solution: xh = 80.92%
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Now for converting these mol% to mass%, take 1 mol basis for the solution and multiplying it by molar mass:
mp = 0.1908 mol 72.15 g/mol
= 13.766 g
mh = 0.8092 mol 86.18 g/mol
= 69.737 g
-
Mass% of Pentane solution = 13.766/(13.766+69.737)
= 16.49%
-
Mass% of Hexane solution = 83.51%
