About Half of the Sodium Carbonate Produced Is Used in Making

question 81

Multiple Choice

About half of the sodium carbonate produced is used in making glass products because it lowers the melting point of sand, the major component of glass. When sodium carbonate is added to water it hydrolyses according to the following reactions. CO₃^2-(aq) + H₂O(l) HCO₃^-(aq) + OH^-(aq) K₁
HCO₃(aq) + H₂O(l) H₂CO₃(aq) + OH^-(aq) K₂
These can be combined to yield
CO₃^2-(aq) + 2H₂O(l) H₂CO₃(aq) + 2OH^-(aq) K₃
What is the value of K₃?

• A) K₁ × K₂
• B) K₁ ÷ K₂
• C) K₁ + K₂
• D) K₁ - K₂
• E) (K₁K₂)²

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Definitions:

Stimulus Generalisation

The process by which a conditioned response (CR) starts occurring in response to stimuli that are similar, but not identical, to the original conditioned stimulus (CS).

Stimulus Generalisation

The tendency for a response that has been conditioned to one stimulus to be elicited by similar stimuli.

Stimulus Discrimination

The learned ability to distinguish between a conditioned stimulus and other stimuli that do not signal an unconditioned stimulus.

Stimulus Discrimination

The learned ability to differentiate between a conditioned stimulus and other stimuli that are not paired with an unconditioned stimulus.