Calculate the mass of 0.0122 moles of: a) Si3N4 b) (CH3)3 N
a.) 0.0122mol x 140gSi3N4 = 1.708 molSi3N4
b.) 0.0122mol x 59g(CH3)3N =0.7198 mol(CH3)3N
a) Si3N4:
Well, Si3N4 might sound like a fancy name, but it's still got some mass to it. The atomic weight of Si is approximately 28 g/mol, and the atomic weight of N is about 14 g/mol. So, in one mole of Si3N4, we have 3 moles of Si and 4 moles of N. Adding up the masses, we get:
(3 x 28 g/mol) + (4 x 14 g/mol) = 84 g/mol + 56 g/mol = 140 g/mol.
Now, since you have 0.0122 moles of Si3N4, just multiply the mole amount by the molar mass:
0.0122 moles x 140 g/mol = 1.71 g (approximately).
b) (CH3)3 N:
Ah, the lovely compound known as trimethylamine (CH3)3 N. To calculate the mass of (CH3)3 N, we need to add up the atomic masses of all the atoms present. Let's break it down: we have 3 carbon atoms (C) with an atomic weight of roughly 12 g/mol each, 9 hydrogen atoms (H) with an atomic weight of approximately 1 g/mol each, and 1 nitrogen atom (N) with an atomic weight of around 14 g/mol. Adding them all up, we get:
(3 x 12 g/mol) + (9 x 1 g/mol) + 14 g/mol = 36 g/mol + 9 g/mol + 14 g/mol = 59 g/mol.
Since you have 0.0122 moles of (CH3)3 N, multiply the mole amount by the molar mass:
0.0122 moles x 59 g/mol = 0.72 g (approximately).
So, the mass of 0.0122 moles of a) Si3N4 is approximately 1.71 g, and b) (CH3)3 N is approximately 0.72 g.
To calculate the mass of a substance, you need to know the molar mass. The molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). Let's calculate the mass of 0.0122 moles of each compound:
a) Si3N4:
The molar mass of Si3N4 can be calculated by summing the atomic masses of the elements in the compound. The atomic masses are as follows:
- Si (Silicon): 28.0855 g/mol
- N (Nitrogen): 14.0067 g/mol
Molar mass of Si3N4 = (3 * Si) + (4 * N)
= (3 * 28.0855) + (4 * 14.0067)
= 84.2565 + 56.0268
= 140.2833 g/mol
Now, we can calculate the mass of 0.0122 moles of Si3N4:
Mass = moles * molar mass
= 0.0122 * 140.2833
≈ 1.712 g
Therefore, the mass of 0.0122 moles of Si3N4 is approximately 1.712 grams.
b) (CH3)3N:
The molar mass of (CH3)3N can also be calculated by summing the atomic masses of the elements in the compound. The atomic masses are as follows:
- C (Carbon): 12.0107 g/mol
- H (Hydrogen): 1.0079 g/mol
- N (Nitrogen): 14.0067 g/mol
Molar mass of (CH3)3N = (3 * C) + (9 * H) + N
= (3 * 12.0107) + (9 * 1.0079) + 14.0067
= 36.0321 + 9.0711 + 14.0067
= 59.1099 g/mol
Now, we can calculate the mass of 0.0122 moles of (CH3)3N:
Mass = moles * molar mass
= 0.0122 * 59.1099
≈ 0.721 g
Therefore, the mass of 0.0122 moles of (CH3)3N is approximately 0.721 grams.
To calculate the mass of a substance given the number of moles, you need to know the molar mass of the substance. The molar mass is the mass of one mole of a substance and is expressed in grams per mole (g/mol). We can find the molar mass by summing up the atomic masses of the individual atoms in the chemical formula.
a) Silicon Nitride (Si3N4):
To calculate the molar mass of Si3N4, we need to look up the atomic masses of silicon (Si) and nitrogen (N) from the periodic table.
- The atomic mass of Si is approximately 28.09 g/mol.
- The atomic mass of N is approximately 14.01 g/mol.
Now, multiply the number of moles (0.0122 mol) by the molar mass (Si3N4) to get the mass:
Mass = 0.0122 mol * molar mass(Si3N4)
The molar mass of Si3N4 is found by multiplying the atomic mass of Si by 3 (there are three Si atoms) and adding it to the atomic mass of N times 4 (since there are four N atoms).
Molar mass(Si3N4) = (3 * atomic mass(Si)) + (4 * atomic mass(N))
b) Trimethylamine (CH3)3 N:
Now, let's calculate the molar mass of (CH3)3N.
- The atomic mass of C is approximately 12.01 g/mol.
- The atomic mass of H is approximately 1.01 g/mol.
- The atomic mass of N is approximately 14.01 g/mol.
Multiply the number of moles (0.0122 mol) by the molar mass ((CH3)3N) to get the mass:
Mass = 0.0122 mol * molar mass((CH3)3N)
The molar mass of (CH3)3N is found by summing up the atomic masses of the individual atoms in the formula.
Molar mass((CH3)3N) = (3 * atomic mass(C)) + (9 * atomic mass(H)) + atomic mass(N)
Using the molar mass, you can now calculate the mass of 0.0122 moles of each substance by substituting the values into the respective formula.