In a reaction, 25 g of reactant AB breaks down into 10g of Product A and an unknown amount of Product B. What is the mass of product B?

Mass of product B  = 15g

Explanation:

Reaction:

          AB →  A   +   B

Mass of AB  = 25g

Mass of A = 10g

Unknown:

Mass of B = ?

Solution:

Based on the law of conservation of matter "matter is neither created nor destroyed but transformed from one form to another in a chemical reaction".

 The amount of product  = amount of reactant

  Mass of AB  = Mass of A + Mass of B

  Now;

    Mass of Product B  = Mass of AB  - Mass of A

     Mass of product B   = 25  - 10  = 15g

Mass of product B  = 15g

b. examine and describe cells