given a 10.0g sample of MgCO3*5H2O, what weight of anhydrous magnesium carbonate can be obtained after driving off the water?
48.4%?
I wasn't sure how to go about finding the answer to this..
I didn't work this, however, I see your answer is 48 percent. 48 percent of what? You have to answer in grams, that is the question.
well 48.4% is the percentage of water in the sample, I believe. So would I subtract that from the whole sample until I isolate the magnesium?
To find the weight of anhydrous magnesium carbonate that can be obtained after driving off the water, you need to understand the concept of percent composition and molar mass. Here's how you can solve this problem step by step:
Step 1: Calculate the molar mass of magnesium carbonate pentahydrate (MgCO3*5H2O).
- The molar mass of Mg = 24.31 g/mol
- The molar mass of C = 12.01 g/mol
- The molar mass of O = 16.00 g/mol
- The molar mass of H2O = 2 * (1.01 g/mol) + 16.00 g/mol = 18.02 g/mol
To find the molar mass of MgCO3*5H2O, multiply the molar mass of each element by its respective number of atoms and add them up:
Molar mass of MgCO3*5H2O = (24.31 g/mol) + (12.01 g/mol) + (3 * 16.00 g/mol) + (5 * 18.02 g/mol)
Step 2: Calculate the molar mass of anhydrous magnesium carbonate (MgCO3).
- The molar mass of Mg = 24.31 g/mol
- The molar mass of C = 12.01 g/mol
- The molar mass of O = 16.00 g/mol
To find the molar mass of MgCO3, multiply the molar mass of each element by its respective number of atoms and add them up:
Molar mass of MgCO3 = (24.31 g/mol) + (12.01 g/mol) + (3 * 16.00 g/mol)
Step 3: Calculate the percent composition of anhydrous magnesium carbonate (MgCO3).
- Divide the molar mass of MgCO3 by the molar mass of MgCO3*5H2O.
- Multiply the result by 100 to get the percent composition.
Percent composition = (Molar mass of MgCO3 / Molar mass of MgCO3*5H2O) * 100
Step 4: Determine the weight of anhydrous magnesium carbonate obtained.
- Multiply the weight of the given sample (10.0g) by the percent composition obtained in Step 3.
Weight of anhydrous magnesium carbonate = Percent composition * Given sample weight
So, to find the weight of anhydrous magnesium carbonate obtained, plug in the given numbers into the above equations and solve for the answer.