Question

What is the significance of writing physical states in a chemical equation?

• A. To provide information about the physical form of substances
• B. To show the mass of reactants and products
• C. To balance the equation more accurately
• D. To indicate the catalyst used in the reaction

Hint:

Pay attention to the physical states when interpreting a chemical equation, as they can provide clues about the reaction conditions and the properties of the substances. For example, (aq) indicates that the substance is dissolved in water, which can influence its reactivity.

Answer 1

The Correct Option is A

Step 1: Recall the components of a balanced chemical equation.
A balanced chemical equation shows the chemical formulas of the reactants and products, along with their stoichiometric coefficients, ensuring that the number of atoms of each element is the same on both sides of the equation.
Step 2: Understand the notation used to indicate physical states.
In a chemical equation, the physical state of each substance is often indicated using abbreviations in parentheses following the chemical formula:

• (s) for solid
• (l) for liquid
• (g) for gas
• (aq) for aqueous solution (dissolved in water)

Step 3: Analyze the significance of these physical state symbols.

1. 
   To provide information about the physical form of substances:
   Writing the physical states provides crucial information about whether the reactants and products are solids, liquids, gases, or dissolved in water. This can be important for understanding the reaction conditions and the nature of the substances involved.
2. 
   To show the mass of reactants and products:
   The physical states do not directly indicate the mass of the reactants and products. The mass is determined by the molar masses and the stoichiometric coefficients in the balanced equation.
3. 
   To balance the equation more accurately:
   Balancing a chemical equation involves ensuring the conservation of atoms. The physical states do not affect the balancing of the number of atoms of each element.
4. 
   To indicate the catalyst used in the reaction:
   The catalyst used in a reaction is typically written above or below the reaction arrow and is not indicated by the physical state symbols of the reactants or products.

Step 4: Identify the primary significance of writing physical states.
The main significance of writing physical states in a chemical equation is to provide information about the physical form (solid, liquid, gas, or aqueous solution) of the reactants and products involved in the reaction.