Calculate The Molar Mass of The Following Substances Nh4 2cr2o7
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Reviewed by Calculator Editorial Team
Calculating the molar mass of NH4 2Cr2O7 (ammonium dichromate) is essential for stoichiometry problems in chemistry. This guide explains the calculation process, provides a calculator, and includes a worked example.
How to Calculate Molar Mass
The molar mass of a compound is the sum of the atomic masses of all atoms in its chemical formula. For NH4 2Cr2O7:
- Identify each element and its count in the formula
- Find the atomic mass of each element from the periodic table
- Multiply each atomic mass by its count in the formula
- Sum all the values to get the molar mass
Remember that the subscript 2 in Cr2O7 means there are two chromium atoms and seven oxygen atoms, not two chromium atoms and two oxygen atoms.
Molar Mass Formula
Molar Mass = (Count of N × Atomic Mass of N) + (Count of H × Atomic Mass of H) + (Count of Cr × Atomic Mass of Cr) + (Count of O × Atomic Mass of O)
For NH4 2Cr2O7:
- Nitrogen (N): 1 atom × 14.0067 g/mol
- Hydrogen (H): 4 atoms × 1.00794 g/mol
- Chromium (Cr): 2 atoms × 51.9961 g/mol
- Oxygen (O): 7 atoms × 15.9994 g/mol
Worked Example
Let's calculate the molar mass of NH4 2Cr2O7 step by step:
- Nitrogen: 1 × 14.0067 = 14.0067 g/mol
- Hydrogen: 4 × 1.00794 = 4.03176 g/mol
- Chromium: 2 × 51.9961 = 103.9922 g/mol
- Oxygen: 7 × 15.9994 = 111.9958 g/mol
Total molar mass = 14.0067 + 4.03176 + 103.9922 + 111.9958 = 234.02646 g/mol
The molar mass of NH4 2Cr2O7 is approximately 234.03 g/mol when rounded to two decimal places.
FAQ
What is the molar mass of NH4 2Cr2O7?
The molar mass of NH4 2Cr2O7 is approximately 234.03 g/mol. You can calculate this using the formula method described in this guide or our online calculator.
How do I find the atomic masses for each element?
You can find atomic masses in the periodic table. For this calculation, we used the following values: N (14.0067), H (1.00794), Cr (51.9961), and O (15.9994).
Why is the molar mass important in chemistry?
Molar mass is crucial for stoichiometry calculations, determining reaction quantities, and understanding chemical proportions. It helps chemists predict how much product will form from given reactants.