The formula weight of diethyl ether is 74.0 amu. What is the weight of 4.25 ´ 10 20 molecules of diethyl ether?
To calculate the weight of a certain number of molecules of a compound, you need to use the Avogadro's number and the molar mass (also known as molecular weight or formula weight) of the compound. Here's how you can determine the weight of 4.25 × 10^20 molecules of diethyl ether:
Step 1: Determine the molar mass (formula weight) of diethyl ether
Given that the formula weight of diethyl ether is 74.0 amu (atomic mass units).
Step 2: Convert the number of molecules to moles using Avogadro's number
Avogadro's number represents the number of particles (molecules, atoms, etc.) in one mole of a substance, and it is approximately 6.022 × 10^23.
To convert the number of molecules to moles, divide the given number of molecules by Avogadro's number:
Number of moles = (Number of molecules) / Avogadro's number
In this case:
Number of moles = 4.25 × 10^20 molecules / (6.022 × 10^23 molecules/mole)
Step 3: Calculate the weight using the molar mass
The weight (in grams) can be calculated by multiplying the number of moles by the molar mass:
Weight = (Number of moles) × (Molar mass)
In this case:
Weight = (Number of moles) × (Formula weight)
Now let's plug in the values to calculate the weight:
Number of moles = 4.25 × 10^20 molecules / (6.022 × 10^23 molecules/mole)
Weight = (4.25 × 10^20 molecules / (6.022 × 10^23 molecules/mole)) × (74.0 amu)
Make sure to cancel out units where appropriate (molecules/mole) to get the final result in grams.