Determine the number of moles of each specified atom or ion in the given samples of the following compounds.( Hint: the formula tells you how many atoms or ions are in each molecule of formula unit.)
a. O atom in 3.161x10^21 molecules of CO2
b. C atom in 3.161x10^21 molecules of CO2
c. O atom in 2.2222x10^24 molecules of CO2
d. K^+ ions in 5.324 *10^16 formula units of KNO2
e. CL^ - ions in 1.000 x 1o^14 formula units of MgCl2
f. N atoms in 2.000 * 10^14 formula units of Ca (NO3)2
g. O atoms in 4.999 x 10^25 formula units of Mg3(PO4)2
a. To determine the number of moles of O atoms in 3.161x10^21 molecules of CO2, we need to use the ratio of O atoms to CO2 molecules in the compound.
The formula for CO2 tells us that there are 2 O atoms in 1 molecule of CO2.
Therefore, the number of O atoms in 3.161x10^21 molecules of CO2 is:
3.161x10^21 molecules of CO2 * (2 O atoms / 1 molecule of CO2) = 6.322x10^21 O atoms
b. To determine the number of moles of C atoms in 3.161x10^21 molecules of CO2, we follow a similar approach.
The formula for CO2 tells us that there is 1 C atom in 1 molecule of CO2.
Therefore, the number of C atoms in 3.161x10^21 molecules of CO2 is:
3.161x10^21 molecules of CO2 * (1 C atom / 1 molecule of CO2) = 3.161x10^21 C atoms
c. Similar to part a, we can use the ratio of O atoms to CO2 molecules to determine the number of O atoms in 2.2222x10^24 molecules of CO2.
The formula for CO2 tells us that there are 2 O atoms in 1 molecule of CO2.
Therefore, the number of O atoms in 2.2222x10^24 molecules of CO2 is:
2.2222x10^24 molecules of CO2 * (2 O atoms / 1 molecule of CO2) = 4.4444x10^24 O atoms
d. To determine the number of K+ ions in 5.324*10^16 formula units of KNO2, we need to use the ratio of K+ ions to formula units in the compound.
The formula for KNO2 tells us that there is 1 K+ ion in 1 formula unit of KNO2.
Therefore, the number of K+ ions in 5.324*10^16 formula units of KNO2 is:
5.324*10^16 formula units of KNO2 * (1 K+ ion / 1 formula unit of KNO2) = 5.324*10^16 K+ ions
e. To determine the number of Cl- ions in 1.000x10^14 formula units of MgCl2, we need to use the ratio of Cl- ions to formula units in the compound.
The formula for MgCl2 tells us that there are 2 Cl- ions in 1 formula unit of MgCl2.
Therefore, the number of Cl- ions in 1.000x10^14 formula units of MgCl2 is:
1.000x10^14 formula units of MgCl2 * (2 Cl- ions / 1 formula unit of MgCl2) = 2.000x10^14 Cl- ions
f. To determine the number of N atoms in 2.000x10^14 formula units of Ca(NO3)2, we need to use the ratio of N atoms to formula units in the compound.
The formula for Ca(NO3)2 tells us that there are 2 N atoms in 1 formula unit of Ca(NO3)2.
Therefore, the number of N atoms in 2.000x10^14 formula units of Ca(NO3)2 is:
2.000x10^14 formula units of Ca(NO3)2 * (2 N atoms / 1 formula unit of Ca(NO3)2) = 4.000x10^14 N atoms
g. To determine the number of O atoms in 4.999x10^25 formula units of Mg3(PO4)2, we need to use the ratio of O atoms to formula units in the compound.
The formula for Mg3(PO4)2 tells us that there are 8 O atoms in 1 formula unit of Mg3(PO4)2.
Therefore, the number of O atoms in 4.999x10^25 formula units of Mg3(PO4)2 is:
4.999x10^25 formula units of Mg3(PO4)2 * (8 O atoms / 1 formula unit of Mg3(PO4)2) = 3.9992x10^26 O atoms
To determine the number of moles of each specified atom or ion in the given samples of the compounds, we need to use Avogadro's number and the formula of each compound.
Avogadro's number is 6.022 x 10^23 representative particles per mole. This means that for every mole of a substance, there are 6.022 x 10^23 atoms, molecules, or ions, depending on the substance.
Let's solve each part:
a. O atom in 3.161x10^21 molecules of CO2:
CO2 has 1 carbon atom (C) and 2 oxygen atoms (O) in each molecule.
- First, we calculate the number of moles of CO2:
Number of moles of CO2 = Number of molecules of CO2 / Avogadro's number
Number of moles of CO2 = 3.161x10^21 / (6.022 x 10^23)
Number of moles of CO2 ≈ 0.00525 moles
- Since there are 2 oxygen atoms in each molecule of CO2, we multiply the number of moles of CO2 by 2 to get the number of moles of oxygen atoms:
Number of moles of O atoms = Number of moles of CO2 * 2
Number of moles of O atoms ≈ 0.00525 moles * 2
Number of moles of O atoms ≈ 0.0105 moles
Therefore, there are approximately 0.0105 moles of oxygen atoms in 3.161x10^21 molecules of CO2.
b. C atom in 3.161x10^21 molecules of CO2:
Using the same approach as above, we find that the number of moles of carbon atoms is equal to the number of moles of CO2:
Number of moles of C atoms ≈ 0.00525 moles
Therefore, there are approximately 0.00525 moles of carbon atoms in 3.161x10^21 molecules of CO2.
c. O atom in 2.2222x10^24 molecules of CO2:
Following the same steps as part (a), we find:
Number of moles of CO2 = 2.2222x10^24 / (6.022 x 10^23)
Number of moles of CO2 ≈ 3.689 moles
Number of moles of O atoms = Number of moles of CO2 * 2
Number of moles of O atoms ≈ 3.689 moles * 2
Number of moles of O atoms ≈ 7.378 moles
Therefore, there are approximately 7.378 moles of oxygen atoms in 2.2222x10^24 molecules of CO2.
d. K^+ ions in 5.324 * 10^16 formula units of KNO2:
KNO2 has 1 potassium ion (K^+) in each formula unit.
Number of moles of K^+ ions = Number of formula units of KNO2 / Avogadro's number
Number of moles of K^+ ions = 5.324 * 10^16 / (6.022 x 10^23)
Number of moles of K^+ ions ≈ 0.000008856 moles
Therefore, there are approximately 0.000008856 moles of potassium ions in 5.324 * 10^16 formula units of KNO2.
e. Cl^- ions in 1.000 x 10^14 formula units of MgCl2:
MgCl2 has 2 chloride ions (Cl^-) in each formula unit.
Number of moles of Cl^- ions = Number of formula units of MgCl2 * 2 / Avogadro's number
Number of moles of Cl^- ions = 1.000 x 10^14 * 2 / (6.022 x 10^23)
Number of moles of Cl^- ions ≈ 0.000001658 moles
Therefore, there are approximately 0.000001658 moles of chloride ions in 1.000 x 10^14 formula units of MgCl2.
f. N atoms in 2.000 * 10^14 formula units of Ca(NO3)2:
Ca(NO3)2 has 2 nitrogen atoms (N) in each formula unit.
Number of moles of N atoms = Number of formula units of Ca(NO3)2 * 2 / Avogadro's number
Number of moles of N atoms = 2.000 * 10^14 * 2 / (6.022 x 10^23)
Number of moles of N atoms ≈ 0.000006644 moles
Therefore, there are approximately 0.000006644 moles of nitrogen atoms in 2.000 * 10^14 formula units of Ca(NO3)2.
g. O atoms in 4.999 x 10^25 formula units of Mg3(PO4)2:
Mg3(PO4)2 has 8 oxygen atoms (O) in each formula unit.
Number of moles of O atoms = Number of formula units of Mg3(PO4)2 * 8 / Avogadro's number
Number of moles of O atoms = 4.999 x 10^25 * 8 / (6.022 x 10^23)
Number of moles of O atoms ≈ 66.078 moles
Therefore, there are approximately 66.078 moles of oxygen atoms in 4.999 x 10^25 formula units of Mg3(PO4)2.
There are 6.02 x 10^23 molecules in a mole of molecules or atoms in a mole of atoms. Here is how you do the first one.
3.161 x 10^21 molecules CO2 x (1 mole CO2 molecules/6.02 x 10^23 molecules CO2) x (2 atoms O/1 molecule CO2) = ?? moles O atoms in 3.161 x 10^23 molecules CO2.
The others are done the same way. Note the use of the factors. They all work this way, even with different problems (of course the factors are different for different kinds of problems).