1.How many atoms are in a sample of copper with a mass of 18.46 grams?
2.How many formula units are in a sample of salt with a mass of 67.69 grams?
3.How many molecules are in a sample of water with a mass of 44.99 grams?
4.What is the mass in grams of 0.250 moles Mg?
5.How many moles are there in 48.096 grams of sulfur?
6.What is the mass of 24.6 formula units of magnesium oxide?
7.How many molecules of dinitrogen pentoxide are contained in 123.46 grams of dinitrogen pentoxide?
See your post above. These are the same type.
1. To determine the number of atoms in a sample of copper, we'll need to use the molar mass of copper and Avogadro's number. The molar mass of copper is 63.55 grams/mol, and Avogadro's number is 6.022 x 10^23 atoms/mol.
First, we'll calculate the number of moles of copper by dividing the mass given (18.46 grams) by the molar mass of copper (63.55 grams/mol):
moles of copper = 18.46 g / 63.55 g/mol
Next, to find the number of atoms, we'll multiply the number of moles by Avogadro's number:
number of atoms = moles of copper * Avogadro's number
2. To find the number of formula units in a sample of salt, we'll need to use the molar mass of salt and Avogadro's number. The molar mass of salt (sodium chloride) is 58.44 grams/mol, and Avogadro's number is 6.022 x 10^23 formula units/mol.
First, calculate the number of moles of salt by dividing the given mass (67.69 grams) by the molar mass of salt (58.44 grams/mol):
moles of salt = 67.69 g / 58.44 g/mol
Next, multiply the number of moles by Avogadro's number to find the number of formula units:
number of formula units = moles of salt * Avogadro's number
3. To determine the number of molecules in a sample of water, we'll need to use the molar mass of water and Avogadro's number. The molar mass of water (H2O) is 18.015 grams/mol, and Avogadro's number is 6.022 x 10^23 molecules/mol.
First, calculate the number of moles of water by dividing the given mass (44.99 grams) by the molar mass of water (18.015 grams/mol):
moles of water = 44.99 g / 18.015 g/mol
Next, multiply the number of moles by Avogadro's number to find the number of molecules:
number of molecules = moles of water * Avogadro's number
4. The molar mass of magnesium (Mg) is 24.305 grams/mol. To find the mass of 0.250 moles of magnesium, multiply the molar mass by the number of moles:
mass of magnesium = 0.250 moles * 24.305 grams/mol
5. To find the number of moles in 48.096 grams of sulfur, we need to divide the given mass by the molar mass of sulfur. The molar mass of sulfur (S) is 32.06 grams/mol:
moles of sulfur = 48.096 g / 32.06 g/mol
6. To determine the mass of 24.6 formula units of magnesium oxide, we'll need to know the molar mass of magnesium oxide (MgO). The molar mass of magnesium oxide is 40.3044 grams/mol.
First, calculate the number of moles of magnesium oxide using Avogadro's number:
moles of magnesium oxide = 24.6 formula units * (1 mol/Avogadro's number)
Next, multiply the number of moles by the molar mass of magnesium oxide to find the mass:
mass of magnesium oxide = moles of magnesium oxide * 40.3044 grams/mol
7. To find the number of molecules of dinitrogen pentoxide in 123.46 grams of dinitrogen pentoxide, we need to use the molar mass of dinitrogen pentoxide (N2O5) and Avogadro's number.
First, calculate the number of moles of dinitrogen pentoxide by dividing the given mass (123.46 grams) by the molar mass of dinitrogen pentoxide:
moles of dinitrogen pentoxide = 123.46 g / molar mass of dinitrogen pentoxide
Next, multiply the number of moles by Avogadro's number to find the number of molecules:
number of molecules = moles of dinitrogen pentoxide * Avogadro's number