Na2CO3 is the chemical formula for sodium carbonate. Its common name is washing soda (in the hydrated form Na2CO3·10H2O) or soda ash (in the anhydrous form). The molecular mass of Na2CO3 is 106 g/mol. It is a white, crystalline, water-soluble salt widely used in industrial processes, cleaning, and the glass industry.
Na2CO3 chemical name: sodium carbonate; common name: washing soda (hydrated form).
Molecular mass of Na2CO3 = 106 g/mol (2×23 + 12 + 3×16).
Hydrated form: Na2CO3·10H2O (washing soda), molecular mass = 286 g/mol.
Na2CO3 solution is alkaline (pH ~11.6) — turns red litmus blue.
Na2CO3·10H2O is efflorescent — loses water of crystallisation on exposure to dry air.
Used extensively in glass manufacturing, detergents, and water treatment.
Reacts with acids to produce CO2: Na2CO3 + 2HCl → 2NaCl + H2O + CO2.
Anhydrous Na2CO3 is called soda ash; monohydrate is called crystal carbonate.
Na2CO3 is the chemical formula for sodium carbonate. It contains two sodium (Na) atoms, one carbon (C) atom, and three oxygen (O) atoms. Common names include:
Sodium carbonate is a salt of a strong base (NaOH) and a weak acid (H2CO3), making its aqueous solution alkaline (basic). Its solutions turn red litmus paper blue.
The molecular mass of Na2CO3 is calculated as follows:
Na2CO3: 2 × Na + 1 × C + 3 × O = 2 × 23 + 12 + 3 × 16 = 46 + 12 + 48 = 106 g/mol
For the decahydrate (washing soda), Na2CO3·10H2O: = 106 + 10 × 18 = 106 + 180 = 286 g/mol
Atomic masses: Na = 23, C = 12, O = 16, H = 1.
Physical properties of Na2CO3:
Efflorescence: Na2CO3·10H2O loses water of crystallisation on exposure to air, converting to the monohydrate or anhydrous form — a process called efflorescence.
Key chemical reactions of Na2CO3:
Reaction with acids (neutralisation): Na2CO3 + H2SO4 → Na2SO4 + H2O + CO2 Na2CO3 + 2HCl → 2NaCl + H2O + CO2
Reaction with calcium hydroxide (Solvay process-related): Na2CO3 + Ca(OH)2 → 2NaOH + CaCO3↓
Hydrolysis in water (alkaline reaction): CO3²⁻ + H2O ⇌ HCO3⁻ + OH⁻ (This is why Na2CO3 solution is alkaline)
Heating: Na2CO3 is thermally stable and does not decompose easily, unlike NaHCO3.
Na2CO3 has extensive industrial and domestic uses:
Na2CO3 is sodium carbonate. The anhydrous form is known as soda ash, and the hydrated form Na2CO3·10H2O is commonly called washing soda.
The molecular mass of Na2CO3 is 106 g/mol. Calculation: 2×23 (Na) + 12 (C) + 3×16 (O) = 46 + 12 + 48 = 106 g/mol.
Na2CO3 is a salt of strong base (NaOH) and weak acid (H2CO3). In water, carbonate ion hydrolyses: CO3²⁻ + H2O ⇌ HCO3⁻ + OH⁻, releasing OH⁻ ions and making the solution alkaline (pH ~11.6).
NaHCO3 (sodium bicarbonate / baking soda) has one sodium and one hydrogen in the formula, with molecular mass 84 g/mol. Na2CO3 (sodium carbonate / washing soda) has two sodium atoms and molecular mass 106 g/mol. Na2CO3 is more alkaline and thermally more stable than NaHCO3.
Washing soda (Na2CO3·10H2O) is used to soften hard water (by precipitating Ca²⁺ and Mg²⁺), as a cleaning agent in laundry, in glass manufacturing, paper production, and as a laboratory reagent.
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