To find the number of grams, moles, and molecules of acetic acid, we'll follow these steps:
Step 1: Calculate the mass of the given volume of acetic acid.
Step 2: Convert the mass to moles using the molar mass of acetic acid.
Step 3: Calculate the number of molecules using Avogadro's number.
Step 1: Calculate the mass of the given volume of acetic acid.
Density = mass/volume
mass = density × volume
Given density = 1.058 g/mL
Volume = 25 mL
mass = 1.058 g/mL × 25 mL
mass = 26.45 grams
Step 2: Convert the mass to moles using the molar mass of acetic acid.
The molar mass of acetic acid (C₂H₄O₂) can be calculated as follows:
Molar mass (C) = 12.01 g/mol
Molar mass (H) = 1.01 g/mol
Molar mass (O) = 16.00 g/mol
Molar mass (C₂H₄O₂) = 2 × (Molar mass (C)) + 4 × (Molar mass (H)) + 2 × (Molar mass (O))
Molar mass (C₂H₄O₂) = 2 × 12.01 g/mol + 4 × 1.01 g/mol + 2 × 16.00 g/mol
Molar mass (C₂H₄O₂) = 24.02 g/mol + 4.04 g/mol + 32.00 g/mol
Molar mass (C₂H₄O₂) = 60.06 g/mol
Now, we can calculate the number of moles:
moles = mass / molar mass
moles = 26.45 g / 60.06 g/mol
moles ≈ 0.4405 moles
Step 3: Calculate the number of molecules using Avogadro's number.
Avogadro's number (Nₐ) is approximately 6.022 × 10²³ molecules/mol.
Number of molecules = moles × Avogadro's number
Number of molecules = 0.4405 moles × 6.022 × 10²³ molecules/mol
Number of molecules ≈ 2.652 × 10²³ molecules
So, in the given 25 mL of acetic acid, you have approximately:
26.45 grams of acetic acid
0.4405 moles of acetic acid
2.652 × 10²³ molecules of acetic acid.