Why do effervescent tablets dissolve in water? Why do they dissolve faster in hot water? Why do effervescent tablets dissolve slower in carbonated soft drink than they do in water?

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The chemical reaction that occurs when effervescent tablets are placed in water is as follows:

Reaction in Words:

Citric Acid + Sodium Bicarbonate yields Water + Carbon Dioxide + Sodium Citrate

Reaction in Symbols:

~C_6H_8O_7 + ~3NaHCO_3  -> ~3H_2O + ~3CO_2 + ~Na_3C_6H_5O_7

How the Reaction Occurs:

  • Before the...

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The chemical reaction that occurs when effervescent tablets are placed in water is as follows:

Reaction in Words: 

Citric Acid + Sodium Bicarbonate yields Water + Carbon Dioxide + Sodium Citrate

Reaction in Symbols:

~C_6H_8O_7 + ~3NaHCO_3  -> ~3H_2O + ~3CO_2 + ~Na_3C_6H_5O_7

How the Reaction Occurs:

  • Before the tablet is dissolved, the citric acid and sodium bicarbonate are in solid form and unable to react with one another.
  • In order for the citric acid and sodium bicarbonate to react, they must be dissolved in water. Dissolving breaks the two chemicals into their positive and negative ions. This enables them to come in contact and react with one another.

Why do effervescent tablets dissolve in water?

  • Citric acid is an acid and sodium bicarbonate is an ionic substance. Both of these types of substances are soluble in water. When acids and ionic substances are placed in water, the substances break apart into positive and negative ions. Water is a polar molecule. This means it has a positive side and a negative side. These substances are able to dissolve when the positive side of the water molecules interacts with the negative ions and the negative side of the water molecule interacts with the positive ions. When a substance has been dissolved in water, it is called an aqueous solution. 

Why do effervescent tablets dissolve faster in hot water?

  • In order for a reaction between two substances to occur, the substances must come in contact with one another. Anything that increases the probablity that the substances will come in contact with one another will increase the rate of the reaction. As temperature increases, the movement of the substance's particles increases. This makes it more likely that they will come in contact with one another and react. The more the substances are able to come in contact, the faster the reaction will occur.

Why do effervescent tablets dissolve slower in carbonated beverages?

  • The ingredients in effervescent tablets are less soluble in carbonated beverages than in water. Water is often called "the universal solvent" because it is so good at dissolving ions due to its positive and negative sides. Since effervescent tablets are less soluble in carbonated beverages, it takes longer for the tablets to dissolve and enable the reaction to occur.

 

 

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