1. How many moles of oxyen atoms are there in 2 moles of KNO3? 2. How many oxyge
ID: 304482 • Letter: 1
Question
1. How many moles of oxyen atoms are there in 2 moles of KNO3?2. How many oxygen atoms are there in 2.50 moles of O2 molecules?
3. A mole of H2O and a mole of O2 a. Have the same mass b. Contain one molecule each c. Have a mass of 1g each d. Contain the same number of molecules
4. One molecule of sulfur contain 8 sulfur atoms. Then one mole of sulfur molecules will contain a. 8g of sulfur b. 8 moles of sulfur atoms c. 602,000,000,000,000,000,000,000 sulfur atoms d. 8 sulfur atoms
5. How many oxygen atoms are there in 48.0g of O and 48.0g of O2? 1. How many moles of oxyen atoms are there in 2 moles of KNO3?
2. How many oxygen atoms are there in 2.50 moles of O2 molecules?
3. A mole of H2O and a mole of O2 a. Have the same mass b. Contain one molecule each c. Have a mass of 1g each d. Contain the same number of molecules
4. One molecule of sulfur contain 8 sulfur atoms. Then one mole of sulfur molecules will contain a. 8g of sulfur b. 8 moles of sulfur atoms c. 602,000,000,000,000,000,000,000 sulfur atoms d. 8 sulfur atoms
5. How many oxygen atoms are there in 48.0g of O and 48.0g of O2?
2. How many oxygen atoms are there in 2.50 moles of O2 molecules?
3. A mole of H2O and a mole of O2 a. Have the same mass b. Contain one molecule each c. Have a mass of 1g each d. Contain the same number of molecules
4. One molecule of sulfur contain 8 sulfur atoms. Then one mole of sulfur molecules will contain a. 8g of sulfur b. 8 moles of sulfur atoms c. 602,000,000,000,000,000,000,000 sulfur atoms d. 8 sulfur atoms
5. How many oxygen atoms are there in 48.0g of O and 48.0g of O2?
Explanation / Answer
Avogadro's No. = no. of atoms or molecules in 1 mole of atoms or molecules = 6.022 x 1023
1. 2 moles of KNO3 contain 2 x Avogadro's no. of KNO3 molecules = 2 x 6.022 x 1023 molecules
1 molecule of KNO3 contain 3 oxygen atoms. So, 2 x 6.022 x 1023 molecules of KNO3 will contain
3 x 2 x 6.022 x 1023 atoms of oxygen.
No. of moles of oxygen atoms = Total atoms of oxygen / Avogadro's no.
= 3 x 2 x 6.022 x 1023 / 6.022 x 1023
= 6 moles of oxygen atoms
So, 2 moles of KNO3 contains 6 moles of oxygen atoms. Thus, no. of moles of an atom present in a molecule = no. of moles of molecule x no. of atoms present in one molecule.
2. 1 molecule of O2 contains 2 atoms of Oxygen.
2.50 mole of O2 will contain 2 x 2.50 x Avogadro's no. of atoms of oxygen which is
= 2 x 2.50 x 6.022 x 1023 = 3.011 x 1024 atoms of oxygen
3. A mole of H2O and a mole of O2 will contain same no. of molecules which is equal to Avogadro's no. Thus, option d is correct.
4. One molecule of sulphur contains 8 atoms of sulphur. So, 1 mole of sulphur molecules will contain
8 x Avogadro's no. of sulphur atoms = 8 x 6.022 x 1023 = 8 moles of sulphur atoms.
So, option b is correct.
5. Molecular mass of oxygen is 16 g/mol.
moles of O = mass of O / Molecular mass of O
This means that 48 g of O = 48 / 16 moles of O = 3 moles of O
3 moles of O will contain 3 x Avogadro's no. of oxygen atoms = 3 x 6.022 x 1023 oxygen atoms
= 1.8066 x 1024 oxygen atoms
Molecular mass of O2 is 32 g/mol.
moles of O2 = mass of O2 / Molecular mass of O2
This means that 48 g of O2 = 48 / 32 moles of O2 = 1.50 moles of O2
1.50 moles of O2 will contain 1.50 x Avogadro's no. of oxygen atoms
= 1.50 x 6.022 x 1023 oxygen atoms = 9.033 x 1023 oxygen atoms.
comment for queries and provide a feedback
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.