The mole fraction of methanol in the mixture is 0.444
We'll begin by calculating the number of mole of water.
- Molar mass of water = 18 g/mol
Mole = mass / molar mass
Mole of water = 45 / 18
Mole of water = 2.5 moles
Finally, we shall determine the mole fraction of methanol.
- Mole of water = 2.5 moles
- Mole of methanol = 2 moles
- Total mole = 2 + 2.5 = 4.5 moles
Mole fraction of methanol =?
Mole fraction = mole / total mole
Mole fraction of methanol = 2 / 4.5
Mole fraction of methanol = 0.444
Thus, the mole fraction of methanol is 0.444
Learn more about mole fraction:
brainly.com/question/15444997
Answer:
0.15M
Explanation:
The equation for molarity is M= n/L. Where "M" is Molarity, "n" is the number of moles of solute, and "L" is the total liters in solution.
You need to calculate the number of moles from the given grams. The molar mass of KOH is (39.098+ 16 +1.008)= 56.106g. To calculate the mols of KOH, 
× 
= 0.44558... mol, you see that the grams unit cancel out leaving you with mol as the unit.
The volume is given in L already so no need to do any conversion. M= 
= 0.1485M ≈ 0.15M
Answer:
This element is Rubidium (Rb) and has an average atomic mass of 85.468 u
Explanation:
The average mass of an element is calculated by taking the average of the atomic masses of its stable isotopes.
The enitre atomic mass = 100 % or 1
⇒ this consists of X-85 with 72.17 % abundance with atomic massof 84.9118 g/mol
72.17 % = 0.7217
⇒ this consists of X-87 with 27.83 % abundance with atomic mass of 86.9092 g/mol
27.83 % = 0.2783
To calculate the mass of this isotope we use the following:
0.7271 * 84.9118 + 0.2783 * 86.9092 =85.468 g/mol
This element is Rubidium(Rb) and has an average atomic mass of 85.468 u
