In an experiment, 25 g of reactant A reacts with 35 g of reactant B to form 50 g of product C and some amount of product D. What is the mass of product D?

Question

Question

This question was previously asked in

RRB JE CBT 2 (Mechanical Engineering) ReExam Official Paper (Held On: 04 Jun, 2025)

Answer 1

The Correct answer is 10 g.

Key Points

In any chemical reaction, the Law of Conservation of Mass is followed, which states that mass cannot be created or destroyed. This means the total mass of reactants is always equal to the total mass of products.
In this experiment, the mass of the reactants is given as:
- Reactant A: 25 g
- Reactant B: 35 g
The total mass of reactants is therefore 25 g + 35 g = 60 g.
The mass of one product, Product C, is given as 50 g.
To find the mass of the other product, Product D, we apply the Law of Conservation of Mass:
- Total mass of reactants = Total mass of products
- 60 g = 50 g (Product C) + Mass of Product D
From the above equation, the mass of Product D is calculated as:
- Mass of Product D = 60 g - 50 g = 10 g
Hence, the correct answer is 10 g.

Additional Information

Law of Conservation of Mass
- The Law of Conservation of Mass was proposed by Antoine Lavoisier in the late 18th century.
- This law is fundamental in chemistry and ensures that the total mass of reactants in a chemical reaction equals the total mass of products.
- This principle is crucial for understanding chemical equations and ensuring they are balanced.
Applications
- The law is applied in fields like chemical engineering, environmental science, and industrial processes to ensure accurate predictions and calculations.
- It is essential in determining the stoichiometry of reactions and designing chemical processes.