10. To calculate the number of moles in 20 grams of Carbon (12 amu), we need to use the formula:
moles = mass / molar mass
The molar mass of carbon is 12 g/mol. Substituting the given values:
moles = 20 g / 12 g/mol
moles = 1.67 mol
Therefore, there are 1.67 moles of Carbon in 20 grams.
11. To calculate the number of moles in 2.9 grams of Lithium (7 amu), we need to use the formula:
moles = mass / molar mass
The molar mass of Lithium is 7 g/mol. Substituting the given values:
moles = 2.9 g / 7 g/mol
moles = 0.414 mol
Therefore, there are 0.414 moles of Lithium in 2.9 grams.
12. To calculate the number of moles in 0.001 grams of Chlorine (35 amu), we need to use the formula:
moles = mass / molar mass
The molar mass of Chlorine is 35 g/mol. Substituting the given values:
moles = 0.001 g / 35 g/mol
moles = 2.86 x 10^-5 mol
Therefore, there are 2.86 x 10^-5 moles of Chlorine in 0.001 grams.
13. To calculate the number of grams in 10 moles of Beryllium (9 amu), we need to use the formula:
mass = moles x molar mass
The molar mass of Beryllium is 9 g/mol. Substituting the given values:
mass = 10 mol x 9 g/mol
mass = 90 g
Therefore, there are 90 grams of Beryllium in 10 moles.
14. To calculate the number of grams in 3.4 moles of Nitrogen (14 amu), we need to use the formula:
mass = moles x molar mass
The molar mass of Nitrogen is 14 g/mol. Substituting the given values:
mass = 3.4 mol x 14 g/mol
mass = 47.6 g
Therefore, there are 47.6 grams of Nitrogen in 3.4 moles.
15. To calculate the number of grams in 1.5 moles of Hydrogen (1 amu), we need to use the formula:
mass = moles x molar mass
The molar mass of Hydrogen is 1 g/mol. Substituting the given values:
mass = 1.5 mol x 1 g/mol
mass = 1.5 g
Therefore, there are 1.5 grams of Hydrogen in 1.5 moles.
16. To calculate the number of atoms in 10 moles of Helium, we need to use Avogadro's number:
number of atoms = moles x Avogadro's number
Substituting the given values:
number of atoms = 10 mol x 6.022 x 10^23 atoms/mol
number of atoms = 6.022 x 10^24 atoms
Therefore, there are 6.022 x 10^24 atoms in 10 moles of Helium.
17. To find the number of atoms in 0.003 moles of neon, we can use Avogadro's number which is 6.022 x 10^23 atoms per mole.
Number of atoms = 0.003 moles x 6.022 x 10^23 atoms/mole
Number of atoms = 1.8066 x 10^21 atoms
Therefore, there are approximately 1.8066 x 10^21 atoms in 0.003 moles of neon.
18. To find the number of atoms in 2.7 moles of sodium, we can use Avogadro's number again.
Number of atoms = 2.7 moles x 6.022 x 10^23 atoms/mole
Number of atoms = 1.62654 x 10^24 atoms
Therefore, there are approximately 1.62654 x 10^24 atoms in 2.7 moles of sodium.
19. To find the number of atoms in 3.0 grams of boron, we need to first find the number of moles of boron using its atomic mass. The atomic mass of boron is 10.81 g/mol.
Number of moles = 3.0 g / 10.81 g/mol
Number of moles = 0.2773 mol
Then, we can use Avogadro's number to find the number of atoms.
Number of atoms = 0.2773 mol x 6.022 x 10^23 atoms/mole
Number of atoms = 1.6684 x 10^23 atoms
Therefore, there are approximately 1.6684 x 10^23 atoms in 3.0 grams of boron.
20. To find the number of atoms in 5.6 grams of nitrogen, we need to first find the number of moles of nitrogen using its atomic mass. The atomic mass of nitrogen is 14.01 g/mol.
Number of moles = 5.6 g / 14.01 g/mol
Number of moles = 0.3997 mol
Then, we can use Avogadro's number to find the number of atoms.
Number of atoms = 0.3997 mol x 6.022 x 10^23 atoms/mole
Number of atoms = 2.4066 x 10^23 atoms
Therefore, there are approximately 2.4066 x 10^23 atoms in 5.6 grams of nitrogen
Hope this helps!