Using the models of the molecules (black = C, white = H, yellow = S, red = O) determine each of the following for models of compounds 1 and 2: (7.1, 7.2, 7.3) 1.
2.
c. number of moles in 10.0 g

Verified step by step guidance

1. Identify the elements in each molecule using the color code: black = C, white = H, yellow = S, red = O.
2. For the first molecule (top), count the number of each type of atom: 1 sulfur (yellow), 2 oxygens (red). This is likely sulfur dioxide (SO2).
3. For the second molecule (bottom), count the number of each type of atom: 5 carbons (black), 5 hydrogens (white), 1 nitrogen (blue). This is likely pyridine (C5H5N).
4. Calculate the molar mass of each compound using the periodic table: SO2 and C5H5N.
5. Use the formula: number of moles = mass (g) / molar mass (g/mol) to find the number of moles in 10.0 g of each compound.

Key Concepts

Molecular Composition

Molecular composition refers to the types and numbers of atoms present in a molecule. In the context of the question, understanding the molecular formulas of compounds 1 and 2 is essential to determine the number of moles in a given mass. Each atom type (C, H, S, O) contributes to the overall mass and stoichiometry of the compounds.

Molar Mass

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is calculated by summing the atomic masses of all atoms in a molecule. To find the number of moles in 10.0 g of a compound, one must first determine its molar mass and then use the formula: moles = mass (g) / molar mass (g/mol).

Stoichiometry

Stoichiometry is the branch of chemistry that deals with the quantitative relationships between the substances involved in chemical reactions. It allows chemists to predict the amounts of reactants and products based on balanced chemical equations. In this question, stoichiometry is crucial for determining how many moles of each compound are present in the specified mass.