What is the mass, in grams, of each of the following?
a) 2.4×10−3 mol Sb
b) 3.59×10−2 mol Ba
c) 43.6 mol Xe
d) 1.4 mol W
To calculate the mass of a substance in grams, you need to use the molar mass of that substance. The molar mass is the mass of one mole of the substance and is expressed in grams/mole.
a) 2.4×10^(-3) mol Sb:
To determine the molar mass of antimony (Sb), we need to look it up in the periodic table. The molar mass of Sb is approximately 121.76 g/mol.
To calculate the mass, we can use the equation:
Mass = moles x molar mass.
Mass = 2.4×10^(-3) mol x 121.76 g/mol
Mass ≈ 0.292 g (rounded to three decimal places).
b) 3.59×10^(-2) mol Ba:
The molar mass of barium (Ba) can be found in the periodic table and is approximately 137.33 g/mol.
Using the same equation:
Mass = moles x molar mass.
Mass = 3.59×10^(-2) mol x 137.33 g/mol
Mass ≈ 4.93 g.
c) 43.6 mol Xe:
The molar mass of xenon (Xe) is approximately 131.29 g/mol.
Using the equation:
Mass = moles x molar mass.
Mass = 43.6 mol x 131.29 g/mol
Mass ≈ 5712 g.
d) 1.4 mol W:
For tungsten (W), the molar mass can be found in the periodic table and is approximately 183.84 g/mol.
Using the equation:
Mass = moles x molar mass.
Mass = 1.4 mol x 183.84 g/mol
Mass ≈ 257.37 g.
To find the mass of a substance, we can use its molar mass. The molar mass is the mass of one mole of a substance. It is expressed in grams per mole (g/mol).
To find the mass of a given number of moles of a substance, we use the following formula:
Mass (g) = Number of moles (mol) × Molar mass (g/mol)
Let's find the mass for each of the given substances:
a) 2.4×10−3 mol Sb
To find the molar mass of Sb (antimony), we can refer to the periodic table. The atomic mass of Sb is 121.76 g/mol.
Mass (g) = 2.4×10−3 mol × 121.76 g/mol
= 0.291 g
Therefore, the mass of 2.4×10−3 mol of Sb is 0.291 grams.
b) 3.59×10−2 mol Ba
Similarly, let's find the molar mass of Ba (barium). The atomic mass of Ba is 137.33 g/mol.
Mass (g) = 3.59×10−2 mol × 137.33 g/mol
= 4.92 g
Therefore, the mass of 3.59×10−2 mol of Ba is 4.92 grams.
c) 43.6 mol Xe
Now, let's find the molar mass of Xe (xenon). The atomic mass of Xe is 131.29 g/mol.
Mass (g) = 43.6 mol × 131.29 g/mol
= 5703 g
Therefore, the mass of 43.6 mol of Xe is 5703 grams.
d) 1.4 mol W
Finally, let's find the molar mass of W (tungsten). The atomic mass of W is 183.84 g/mol.
Mass (g) = 1.4 mol × 183.84 g/mol
= 257 g
Therefore, the mass of 1.4 mol of W is 257 grams.