Sure! Here are a few calculation examples based on moles and mass:

1. Calculating moles from mass: Example: How many moles are there in 25 grams of water (H2O)? Solution: The molar mass of water is 18 g/mol (2 g/mol for hydrogen and 16 g/mol for oxygen). Therefore, the number of moles can be calculated as: Moles = Mass / Molar mass Moles = 25 g / 18 g/mol Moles ≈ 1.39 mol

2. Calculating mass from moles: Example: What is the mass of 2.5 moles of carbon dioxide (CO2)? Solution: The molar mass of carbon dioxide is 44 g/mol (12 g/mol for carbon and 32 g/mol for oxygen). Therefore, the mass can be calculated as: Mass = Moles x Molar mass Mass = 2.5 mol x 44 g/mol Mass = 110 g

3. Calculating moles from the number of particles: Example: How many moles are there in 3.01 x 10^23 molecules of methane (CH4)? Solution: Avogadro’s number states that 1 mole of any substance contains 6.022 x 10^23 particles. Therefore, the number of moles can be calculated as: Moles = Number of particles / Avogadro’s number Moles = 3.01 x 10^23 molecules / 6.022 x 10^23 molecules/mol Moles ≈ 0.5 mol

4. Calculating the number of particles from moles: Example: How many molecules are there in 0.25 moles of ammonia (NH3)? Solution: Similar to the previous example, we can use Avogadro’s number to calculate the number of particles: Number of particles = Moles x Avogadro’s number Number of particles = 0.25 mol x 6.022 x 10^23 molecules/mol Number of particles ≈ 1.51 x 10^23 molecules

These are just a few examples of calculations involving moles and mass. There are many other types of calculations that can be done using these concepts, depending on the specific problem.