In the Preparation of Oxygen by the Thermal Decomposition of Potassium

question 13

Multiple Choice

In the preparation of oxygen by the thermal decomposition of potassium chlorate shown below,what is the oxidation number change of the atom undergoing reduction?
2 KClO₃(s) → 2 KCl(s) + 3 O₂(g)

• A)- 8
• B)- 6
• C)+ 1
• D)+ 2

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Definitions:

ECG

Electrocardiogram, a test that records the electrical activity of the heart to detect heart problems.

Holter Monitor

A portable device worn by patients to continuously record the heart's electrical activity over 24 hours or longer.

Arrhythmia

An irregularity in the heart's rhythm, which can range from mild to life-threatening conditions.

Heartbeat

The rhythmic contraction and expansion of the heart, especially as felt through the walls of arteries.