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2-Propanol, commonly known as isopropanol or rubbing alcohol, is a colorless compound with the formula \(\mathrm{C}_3\mathrm{H}_7\mathrm{OH}\). It is widely used as a disinfectant and a solvent. To calculate the molar mass of 2-propanol, we start by considering the atomic weights:

• Carbon (C): 12.01 g/mol
• Hydrogen (H): 1.008 g/mol
• Oxygen (O): 16.00 g/mol

The compound contains 3 carbon atoms, 8 hydrogen atoms (including the OH group), and 1 oxygen atom. The molar mass is thus calculated as \[ 3 \times 12.01 + 8 \times 1.008 + 16.00 = 60.10 \ g/mol \] To find out the mass of 0.0255 moles of 2-propanol, use the formula: \[ \text{mass} = \text{moles} \times \text{molar mass} \] Substituting the values, we get \[ 0.0255 \times 60.10 = 1.53355 \ g \]. This shows that 0.0255 moles of 2-propanol has a mass of approximately 1.5336 grams.

Butylated hydroxyanisole, or BHA, is a synthetic antioxidant with the chemical formula \(\mathrm{C}_{11}\mathrm{H}_{16}\mathrm{O}_2\). It is often used to prevent spoilage in food products due to its properties that inhibit oxidation. To determine its molar mass, we use:

• Carbon (C): 12.01 g/mol
• Hydrogen (H): 1.008 g/mol
• Oxygen (O): 16.00 g/mol

The calculation involves 11 carbon atoms, 16 hydrogen atoms, and 2 oxygen atoms, which results in\[ 11 \times 12.01 + 16 \times 1.008 + 2 \times 16.00 = 180.24 \ g/mol \] The mass of 0.0255 moles of BHA can be calculated using: \[ \text{mass} = \text{moles} \times \text{molar mass} \]Thus, \[ 0.0255 \times 180.24 = 4.5951 \ g \]This means 0.0255 moles of BHA weighs approximately 4.595 grams.

Aspirin, chemically known as acetylsalicylic acid, has the formula \(\mathrm{C}_{9}\mathrm{H}_{8}\mathrm{O}_4\). It is one of the most common medications used worldwide for pain relief, reducing fever, and as an anti-inflammatory. The molecular composition comprises the following atomic components:

• Carbon (C): 12.01 g/mol
• Hydrogen (H): 1.008 g/mol
• Oxygen (O): 16.00 g/mol

For the molar mass calculation, aspirin contains 9 carbons, 8 hydrogens, and 4 oxygens, giving\[ 9 \times 12.01 + 8 \times 1.008 + 4 \times 16.00 = 180.16 \ g/mol \] The mass for 0.0255 moles of aspirin can be calculated as:\[ \text{mass} = \text{moles} \times \text{molar mass} \]So,\[ 0.0255 \times 180.16 = 4.59108 \ g \]Hence, 0.0255 moles of aspirin has a mass close to 4.591 grams.

Acetone is a simple organic compound with the formula \((\mathrm{CH}_3)_2\mathrm{CO}\). It is widely known as a solvent and is used in many industrial applications and also as the main ingredient in nail polish remover. The calculation of its molar mass involves:

• Carbon (C): 12.01 g/mol
• Hydrogen (H): 1.008 g/mol
• Oxygen (O): 16.00 g/mol

Acetone consists of 3 carbon atoms, 6 hydrogen atoms, and 1 oxygen atom, leading to\[ 3 \times 12.01 + 6 \times 1.008 + 16.00 = 58.08 \ g/mol \] To find the mass of 0.0255 moles of acetone:\[ \text{mass} = \text{moles} \times \text{molar mass} \] This gives\[ 0.0255 \times 58.08 = 1.48204 \ g \]Thus, 0.0255 moles of acetone weigh about 1.482 grams.