A 0.370mol sample of a metal oxide (M2O3) weighs 55.4g.
How many moles of O?
How many grams of M?
And what is the unknown element M?
Well, let me calculate that for you.
Since each mole of M2O3 has 3 moles of O, we can start by calculating the number of moles of O in the sample.
Given that there are 0.370 moles of M2O3, we can multiply that by 3 to get the moles of O, which is 1.11 moles (0.370 mol × 3).
Now, to calculate the grams of M, we need to subtract the grams of O from the total weight of the sample. So, 55.4 g - (1.11 moles × 16 g/mol) = 37.34 g.
As for the unknown element M, it refers to the metal in the metal oxide (M2O3). Without more information, I cannot determine the specific element M. It could be any metal that forms an oxide with a 2:3 ratio.
I hope these answers brighten up your day!
To find the number of moles of oxygen (O) in the metal oxide (M2O3), we need to calculate the molar ratio of O to M2O3. Based on the chemical formula M2O3, there are three moles of oxygen for every two moles of M2O3.
1. Calculate moles of O:
Moles of O = (0.370 mol M2O3) * (3 mol O / 2 mol M2O3)
= 0.555 mol O
Therefore, there are 0.555 moles of oxygen in the sample.
To find the grams of M (the unknown element), we need to calculate its molar mass. The molar mass of M2O3 can be obtained from the periodic table.
2. Calculate grams of M:
Molar mass of M2O3 = (2 * atomic mass of M) + (3 * atomic mass of O)
55.4 g = (2 * atomic mass of M) + (3 * 16.00 g/mol)
Solving for the atomic mass of M, we get:
(2 * atomic mass of M) = 55.4 g - (3 * 16.00 g/mol)
(2 * atomic mass of M) = 7.4 g
Atomic mass of M = 7.4 g / 2
The atomic mass of M is equal to 3.7 g/mol. Therefore, there are approximately 3.7 grams of M in the sample.
Based on the given information, we cannot determine the identity of the unknown element M without additional details. The chemical formula M2O3 does not reveal the specific identity of the metal M.
To find the number of moles of oxygen (O) in the sample, we need to use the molar ratio between the metal oxide (M2O3) and O. The formula for the metal oxide suggests that there are 3 moles of O for every 2 moles of metal (M) in the compound.
1. Calculate moles of O:
Molar ratio of O to M in M2O3 is 3:2
Moles of O = (0.370 mol of M2O3) × (3 mol of O / 2 mol of M2O3)
Moles of O = 0.370 mol × (3/2)
Moles of O = 0.555 mol
Therefore, there are 0.555 moles of oxygen (O) in the sample.
To find the grams of M (metal), we can use the molar mass of the metal oxide. The atomic masses of the elements can be found on the periodic table.
2. Calculate grams of M:
The molar mass of M2O3 can be calculated as follows:
Molar mass of M2O3 = (molar mass of M × 2) + (molar mass of O × 3)
Given mass of M2O3 = 55.4 g, and the moles of M2O3 (0.370 mol), we can calculate the molar mass of M2O3 as follows:
Molar mass of M2O3 = (55.4 g) / (0.370 mol)
Molar mass of M2O3 = 149.73 g/mol
Since there are 2 moles of M in M2O3, we can find the molar mass of M:
Molar mass of M = (Molar mass of M2O3) / 2
Molar mass of M = 149.73 g/mol / 2
Molar mass of M = 74.87 g/mol
Therefore, the molar mass of the metal (M) is 74.87 g/mol.
Lastly, to determine the unknown element M, we need to find an element with a molar mass close to 74.87 g/mol on the periodic table. The closest match is Yttrium (Y), which has a molar mass of approximately 88.91 g/mol. So the unknown element M in this case is most likely yttrium (Y).
In conclusion:
- The number of moles of O in the sample is 0.555 mol.
- The molar mass of M is 74.87 g/mol.
- The unknown element M is most likely yttrium (Y).
moles x molar mass = grams.
You have moles and grams, calculate molar mass.
I would subtract 48(3x16=48 for 3 atoms O) from the molar mass and divide the remainder by 2 to get the atomic mass of M and from there look on the periodic table for the element M.
moles O = moles M2O3 x (3 atoms O/1 mole M2O3).
Post your work if you get stuck.