Answer :
To find out how many grams are in [tex]\(7.00 \times 10^{22}\)[/tex] molecules of NaOH, we can follow these steps:
1. Understand the Problem: We have a specific number of molecules of NaOH and we need to determine how much this weighs in grams.
2. Use Avogadro's Number: Avogadro's number [tex]\(6.022 \times 10^{23}\)[/tex] molecules/mole tells us how many molecules are in a mole.
3. Calculate Moles of NaOH:
- To find the number of moles, divide the number of molecules by Avogadro's number:
[tex]\[
\text{moles of NaOH} = \frac{7.00 \times 10^{22} \text{ molecules}}{6.022 \times 10^{23} \text{ molecules/mole}}
\][/tex]
- This calculation results in approximately [tex]\(0.116\)[/tex] moles of NaOH.
4. Find the Molar Mass of NaOH:
- The molar mass of sodium hydroxide (NaOH) is approximately 40.00 grams/mole.
5. Calculate Mass in Grams:
- Multiply the number of moles by the molar mass to find the mass in grams:
[tex]\[
\text{mass in grams} = 0.116 \text{ moles} \times 40.00 \text{ grams/mole}
\][/tex]
- This results in roughly [tex]\(4.65\)[/tex] grams.
6. Conclusion:
- Therefore, [tex]\(7.00 \times 10^{22}\)[/tex] molecules of NaOH weigh approximately [tex]\(4.65\)[/tex] grams.
The correct answer is option d) 4.65.
1. Understand the Problem: We have a specific number of molecules of NaOH and we need to determine how much this weighs in grams.
2. Use Avogadro's Number: Avogadro's number [tex]\(6.022 \times 10^{23}\)[/tex] molecules/mole tells us how many molecules are in a mole.
3. Calculate Moles of NaOH:
- To find the number of moles, divide the number of molecules by Avogadro's number:
[tex]\[
\text{moles of NaOH} = \frac{7.00 \times 10^{22} \text{ molecules}}{6.022 \times 10^{23} \text{ molecules/mole}}
\][/tex]
- This calculation results in approximately [tex]\(0.116\)[/tex] moles of NaOH.
4. Find the Molar Mass of NaOH:
- The molar mass of sodium hydroxide (NaOH) is approximately 40.00 grams/mole.
5. Calculate Mass in Grams:
- Multiply the number of moles by the molar mass to find the mass in grams:
[tex]\[
\text{mass in grams} = 0.116 \text{ moles} \times 40.00 \text{ grams/mole}
\][/tex]
- This results in roughly [tex]\(4.65\)[/tex] grams.
6. Conclusion:
- Therefore, [tex]\(7.00 \times 10^{22}\)[/tex] molecules of NaOH weigh approximately [tex]\(4.65\)[/tex] grams.
The correct answer is option d) 4.65.