Final answer:
Magnesium sulfate (MgSO4·nH2O) is a compound that consists of magnesium ions and sulfate ions. It is used in medicine, agriculture, and industrial processes. To calculate the number of water molecules in a sample, the mass of water lost during heating is determined and converted to moles and then to molecules using Avogadro's number.
Step-by-step explanation:
Magnesium sulfate, with the chemical formula MgSO4·nH2O, is a compound that consists of magnesium ions (Mg2+) and sulfate ions (SO42-). The 'n' in the formula represents the number of water molecules bound to the magnesium sulfate crystals, which can vary.
Consideration of magnesium sulfate refers to understanding its properties and applications. For example, magnesium sulfate is commonly used in medicine as a laxative or antacid. It is also used in agriculture as a fertilizer and in various industrial processes.
When a sample of magnesium sulfate containing water molecules is heated, the water evaporates, leaving behind anhydrous magnesium sulfate (MgSO4). To determine the number of water molecules in the original sample, we can use the principle of conservation of mass. Given the initial mass of the sample (5.0 g) and the final mass after water evaporation (2.6 g), we can calculate the mass of water lost and then convert it to the number of water molecules using the molar mass of water (18 g/mol).
Using the given information, the number of water molecules in the original sample can be calculated as follows:
- Calculate the mass of water lost: Mass of water = Initial mass - Final mass
- Convert the mass of water to moles: Moles of water = Mass of water / Molar mass of water
- Convert moles of water to molecules: Molecules of water = Moles of water * Avogadro's number
After performing these calculations, we can determine the number of water molecules in the original sample of magnesium sulfate.