In household chemistry, what is the scientific chemical name of washing soda that is commonly used as a cleaning agent in homes and laboratories?

Introduction / Context:
Many competitive exams ask about the common names and scientific names of basic chemicals used in daily life. Washing soda is a typical household cleaning agent, and knowing its proper chemical name helps you connect common substances with their chemical formulas and properties.

Given Data / Assumptions:
• The substance is called washing soda in common language.
• It is used for washing clothes and as a water softener.
• Options list various sodium and calcium salts that sound similar, such as carbonates and bicarbonates.

Concept / Approach:
Washing soda is hydrated sodium carbonate, usually sodium carbonate decahydrate with the formula Na2CO3·10H2O. The scientific name focuses on the main anion and cation, so it is called sodium carbonate. Sodium bicarbonate (NaHCO3) is called baking soda, used in cooking and antacids. Calcium carbonate is found in limestone and chalk, whereas calcium bicarbonate is present in temporary hard water. Sodium chloride is common table salt. Therefore, among the given options, sodium carbonate is the correct scientific name for washing soda.

Step-by-Step Solution:
Step 1: Recall that washing soda is chemically Na2CO3·10H2O, a hydrated salt of sodium carbonate. Step 2: Note that the correct systematic name for Na2CO3 is sodium carbonate. Step 3: Recognise that sodium bicarbonate, NaHCO3, is a different compound known as baking soda. Step 4: Understand that calcium carbonate and calcium bicarbonate are salts of calcium, not sodium, and therefore cannot be washing soda. Step 5: Eliminate sodium chloride because it is ordinary table salt, not a washing agent called washing soda.

Verification / Alternative check:
Standard chemistry textbooks and exam guides clearly list washing soda as sodium carbonate decahydrate. Detergent formulations also mention sodium carbonate as a component for softening water and removing grease. This cross checking supports the choice of sodium carbonate as the correct answer.

Why Other Options Are Wrong:
Sodium bicarbonate: Known as baking soda, used in baking, fire extinguishers and mild antacids, not primarily called washing soda.
Calcium carbonate: Main component of limestone, marble and chalk, used in cement and construction, not as washing soda.
Calcium bicarbonate: Exists in solution in temporary hard water and is not isolated as a solid washing powder.
Sodium chloride: Common salt used in food, de icing and chemical industry, but not the substance referred to as washing soda.

Common Pitfalls:
The main confusion arises from similar sounding names like carbonate and bicarbonate. Students sometimes mix up washing soda and baking soda or assume that any carbonate can be used for washing. Remember that washing soda is sodium carbonate, while baking soda is sodium bicarbonate, and learn at least a few typical uses of each to avoid mistakes.

Final Answer:
The scientific chemical name of washing soda is Sodium carbonate, usually present as its decahydrate.