4.4.1.5 Concentrated Sulfuric Acid and Water

1.Adding concentrated sulfuric acid to water causes an immediate temperature increase (initial temperature: 19.2 °C) 2.Final temperature: 131.2 °C (an increase of +112 °C)
Adding concentrated sulfuric acid to water causes an immediate temperature increase
(initial temperature: 19.2 °C)
Final temperature: 131.2 °C (an increase of +112 °C)

Photo 1:A test tube containing 100 ml water is equipped with a temperature sensor. The initial temperature is 19.2 °C. 100 ml concentrated sulfuric acid is then added to the water. The temperature increases rapidly.
Photo 2:Within 1 minute, the final temperature of 131.2 °C is reached, a change of +112 °C.

Concentrated sulfuric acid distinguishes itself by its high affinity to water. Mixing the two components results in massive heat emission, which can be traced back to the exothermic production of various hydrates from the sulfuric acid.

Safety Precautions: The sulfuric acid should be added to the water, as illustrated above. Reversing this order and adding the water to the concentrated sulfuric acid can lead to splashing due to the intense production of heat (delayed boiling). Remember the following phrase: "First the water, then the acid, otherwise it won't be placid!"

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