1. What is Molar Mass?

Molar mass is the mass of one mole of a substance (chemical element or chemical compound). For Na2S (sodium sulfide), it's calculated from the atomic masses of sodium (Na) and sulfur (S).

2. How Does the Calculator Work?

The calculator uses the molar mass equation:

Where:

• \( MW \) — Molar mass (g/mol)
• \( m \) — Mass of substance (grams)
• \( n \) — Amount of substance (moles)

Explanation: The equation relates the mass of a substance to its chemical amount in moles. For solutions, moles are calculated from concentration and volume.

3. Importance of Molar Mass Calculation

Details: Molar mass is fundamental in chemistry for stoichiometric calculations, solution preparation, and converting between mass and moles of a substance.

4. Using the Calculator

Tips: Enter the mass of Na2S in grams, solution volume in mL, density in g/mL, and concentration in mol/L. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the theoretical molar mass of Na2S?
A: The theoretical molar mass is approximately 78.04 g/mol (2×Na + S = 2×22.99 + 32.06).

Q2: Why might experimental values differ from theoretical?
A: Experimental values may differ due to impurities, measurement errors, or non-standard conditions.

Q3: How does density factor into the calculation?
A: Density helps verify the mass-volume relationship and solution consistency.

Q4: What units should I use?
A: Use grams for mass, mL for volume, g/mL for density, and mol/L for concentration.

Q5: Can this calculator be used for other compounds?
A: Yes, the same principle applies to any compound when using solution concentration.