How many atoms are there in 6.90 moles of sulfur (S)?
Calculate the molar mass of a compound if 0.411 mole of it has a mass of 185 g.
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Or information on how to?
(a) Multiply the number of moles by 6.02x10^23 atoms/ mole.
(b) If you divide grams by moles you get grams/mole, the atomic mass.
Correction:
(b) If you divide grams by moles you get grams/mole, the molar mass.
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To calculate the number of atoms in a given amount of substance, you need to use Avogadro's number, which is approximately 6.022 x 10^23 atoms per mole.
1. Determine the molar mass of sulfur (S), which is approximately 32.06 g/mol.
2. Multiply the molar mass by the number of moles to obtain the mass of sulfur:
Mass = 6.90 moles * 32.06 g/mol = 221.274 g
3. Divide the mass of sulfur by the molar mass to find the number of moles:
Number of moles of sulfur = 221.274 g / 32.06 g/mol ≈ 6.90 moles
4. Finally, multiply the number of moles by Avogadro's number to calculate the number of atoms:
Number of atoms = 6.90 moles * 6.022 × 10^23 atoms/mol ≈ 4.157 × 10^24 atoms
For the second question, to calculate the molar mass of a compound, you need to know the mass and the number of moles.
1. Divide the mass of the compound by the number of moles to find the molar mass:
Molar Mass = Mass / Number of moles
Molar Mass = 185 g / 0.411 mol ≈ 450 g/mol
Some good websites to find information and calculations related to chemistry include:
- Khan Academy: www.khanacademy.org
- ChemGuide: www.chemguide.co.uk
- Royal Society of Chemistry: www.rsc.org
- Chemistry LibreTexts: chem.libretext.org
These websites provide tutorials, explanations, and practice problems related to various topics in chemistry, including atomic structure, molar mass calculations, and more.
To calculate the number of atoms in 6.90 moles of sulfur (S), we can use Avogadro's number (6.022 × 10^23 atoms/mol).
Step 1: Determine the molar mass of sulfur (S) by referring to the periodic table. The molar mass of sulfur is 32.07 g/mol.
Step 2: Multiply the molar mass of sulfur by the number of moles to find the total mass of sulfur:
Mass of sulfur = Number of moles × Molar mass of sulfur
= 6.90 mol × 32.07 g/mol
= 220.83 g
Step 3: Convert the mass of sulfur to the number of atoms using Avogadro's number:
Number of atoms = Mass of sulfur × Avogadro's number ÷ Molar mass of sulfur
= 220.83 g × 6.022 × 10^23 atoms/mol ÷ 32.07 g/mol
= 4.15 × 10^24 atoms
Therefore, there are approximately 4.15 × 10^24 atoms in 6.90 moles of sulfur (S).
As for sites that can help answer these types of questions or provide information on how to calculate molar mass and atomic quantities, you can try educational websites like Khan Academy, Chem LibreTexts, or Chemistry Stack Exchange. These resources offer explanations, examples, and practice problems to help you understand and solve chemistry-related questions.