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Molar Mass Lab/Molar mass for Fe(OH)3
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Molar Mass of Iron(III) Hydroxide (Fe(OH)3)

Molar Mass of Iron(III) Hydroxide is a frequent exam value for base chemistry, particularly in mole-to-gram and back-conversion questions. Molar Mass of Fe(OH)₃ is 106.87 g/mol, based on 3 element types, with Fe contributing the largest share.

For fast checks, use the calculate molar mass, verify element values in the periodic table with molar mass, or explore more molar mass page.

Molar Mass of Iron(III) Hydroxide is:

106.87 g/mol

Molar Mass of Fe(OH)₃ equals 106.87 g/mol, so 106.87 grams is one mole.

Element Breakdown Table

ElementCountAtomic massCalculationContribution
Iron (Fe)155.841 x 55.8455.84 g/mol
Oxygen (O)316.003 x 16.0048.00 g/mol
Hydrogen (H)31.013 x 1.013.02 g/mol
Final molar mass
55.840 + 48.000 + 3.020
106.87 g/mol

Computing Molar Mass of Iron(III) Hydroxide Step by Step

Molar Mass of Iron(III) Hydroxide: Step-by-Step Calculation

1. Identify Element Counts

Read Fe(OH)3 and list how many atoms of each element are present:

  1. 1 atom of Iron (Fe)
  2. 3 atoms of Oxygen (O)
  3. 3 atoms of Hydrogen (H)

2. Determine Atomic Masses

Look up each element mass from the periodic table:

  1. Iron (Fe) ~= 55.845 g/mol
  2. Oxygen (O) ~= 15.999 g/mol
  3. Hydrogen (H) ~= 1.008 g/mol

3. Multiply Atomic Mass by Quantity

Multiply atom count by atomic mass for each element:

  • Iron (Fe): 1 x 55.845 = 55.840 g/mol
  • Oxygen (O): 3 x 15.999 = 48.000 g/mol
  • Hydrogen (H): 3 x 1.008 = 3.020 g/mol

4. Sum Total Molar Mass

Add all contributions to get the final molar mass in g/mol.

Molar Mass = (1 x 55.845 + 3 x 15.999 + 3 x 1.008)

Molar Mass = 55.840 + 48.000 + 3.020

Molar Mass = 106.870 g/mol

Final rounded value shown on this page: 106.87 g/mol.

Visual Calculation Chart

ElementCountMassCount x massContribution
Iron (Fe)155.8451 x 55.845= 55.840
Oxygen (O)315.9993 x 15.999= 48.000
Hydrogen (H)31.0083 x 1.008= 3.020
Final molar mass
55.840 + 48.000 + 3.020
= 106.870

Easy Way to Remember

Easy way to remember Molar Mass of Iron(III) Hydroxide

  • Molar Mass of Iron(III) Hydroxide: count atoms, multiply masses, and add totals.
  • Write each element in a table so you do not miss subscripts.
  • Keep 2-3 decimals during steps, then round only at the end.

Sample Reactions

TypeReaction
NeutralizationNaOH + HCl → NaCl + H₂O
Acidic oxide absorption₂NaOH + CO₂ → Na₂CO₃ + H₂O

Use these reactions with molar mass when you need the molar mass for each species.

Do You Know?

Iron(III) Hydroxide contains 3 element types: Fe, O, H.

Fe contributes the largest share of this compound's total molar mass.

In Fe(OH)₃, O appears with the highest atom count.

Its molar mass is 106.87 g/mol, which is used directly in gram-to-mole conversions.

A common reaction for Iron(III) Hydroxide is neutralization (NaOH + HCl → NaCl + H₂O).

Why This Compound Matters

Iron(III) Hydroxide is used when studying neutralization, pH control, and measured base preparation.

H make it a common classroom comparison with acids and salts.

Similar calculations can be compared with Iron(II) Hydroxide (Fe(OH)2) and Sodium Hydroxide (NaOH).

Where This Is Used

  • Competitive exams and school chemistry tests.
  • Lab work when preparing measured solutions.
  • Real-world manufacturing and quality checks.

Common Mistakes When Calculating This

  • Skipping subscripts in Fe(OH)₃ and miscounting atoms.
  • Forgetting that parentheses in Fe(OH)₃ multiply the entire grouped part.
  • Mixing up Fe element contribution with total molar mass.
  • Reporting a value without units; final answer should be in g/mol for Iron(III) Hydroxide.

Quick Revision

Formula: Fe(OH)3

Molar Mass: 106.87 g/mol

Key takeaway: count atoms accurately, multiply by atomic masses, and sum only at the end.

Formula Explanation

Fe(OH)3 contains Iron (Fe) (1), Oxygen (O) (3), Hydrogen (H) (3). Add each element contribution to get total molar mass.

Molar Mass = Sum (atomic mass of each element x atom count)

FAQ

The molar mass of Fe(OH)3 is 106.87 g/mol based on atomic masses and atom counts.

Conclusion

Molar Mass of Iron(III) Hydroxide and Molar Mass of Fe(OH)₃ are now easy to revise with this structured page. You can use this method in exams, lab reports, and daily chemistry practice.