The principal component of many kidney stones is calcium oxalate, CaC2O4. A kidney stone recovered from a typical patient contains 8.5 x 10^20 formula units of calcium oxalate. How many moles of CaC2O4 are present in this kidney stone? What is the mass of the kidney stone in grams?

Verified step by step guidance

1. We need to find the number of moles of calcium oxalate (CaC2O4) and its mass in grams, given the number of formula units.
2. Avogadro's number (6.022 x 10^23) tells us how many units (atoms, molecules, formula units, etc.) are in one mole of a substance. To find the moles of CaC2O4, divide the given number of formula units by Avogadro's number.
3. Use the formula: \( \text{moles of CaC}_2\text{O}_4 = \frac{8.5 \times 10^{20}}{6.022 \times 10^{23}} \).
4. Calculate the molar mass by adding the atomic masses of all atoms in the formula: Ca (40.08 g/mol) + C (2 x 12.01 g/mol) + O (4 x 16.00 g/mol).
5. Multiply the number of moles of CaC2O4 by its molar mass to find the mass of the kidney stone in grams.>

Key Concepts

Moles and Avogadro's Number

A mole is a unit in chemistry that represents 6.022 x 10^23 entities, such as atoms or molecules. This number, known as Avogadro's number, allows chemists to convert between the number of particles and the amount of substance in moles. To find the number of moles of calcium oxalate in the kidney stone, one can divide the total number of formula units by Avogadro's number.

Molar Mass

The molar mass of a compound is the mass of one mole of that substance, typically expressed in grams per mole (g/mol). For calcium oxalate (CaC2O4), the molar mass can be calculated by summing the atomic masses of its constituent elements: calcium (Ca), carbon (C), and oxygen (O). This value is essential for converting moles of a substance into grams, which is necessary to determine the mass of the kidney stone.

Stoichiometry

Stoichiometry is the area of chemistry that deals with the quantitative relationships between reactants and products in chemical reactions. It allows chemists to calculate the amounts of substances involved in a reaction based on balanced chemical equations. In this context, stoichiometry is used to relate the number of moles of calcium oxalate to its mass, facilitating the conversion from moles to grams.