Question

1. chlorine is a poisonous gas. sodium reacts explosively with water. when chlorine and sodium react with each other, the product is the salt we sprinkle on our food. which principle does this demonstrate?

a. reactants are more dangerous than products.
b. energy is released by some reactions and absorbed by others.
c. when two reactants form one product, the reaction is spontaneous.
d. products of a chemical reaction have different properties than the reactants.

Explanation:

• Chlorine (\(Cl_2\)) is a poisonous gas and sodium (\(Na\)) reacts explosively with water. But when they react (\(2Na + Cl_2=2NaCl\)), the product is sodium chloride (\(NaCl\), common table - salt).
• This shows that the properties of the reactants (\(Na\) and \(Cl_2\)) are different from the properties of the product (\(NaCl\)).
• Option A: Just because the reactants are dangerous and the product is not, we cannot generalize that reactants are always more dangerous than products. There are reactions where products can be more hazardous.
• Option B: The problem does not mention anything about energy release or absorption.
• Option C: The spontaneity of a reaction (whether it occurs without external intervention) is not indicated in the problem description.
• Option D: This is correct as the example clearly shows a change in properties from reactants to products.

Answer:

D. Products of a chemical reaction have different properties than the reactants.