Why is the vacuum distillation desiccant first anhydrous calcium chloride, then sodium hydroxide, and finally paraffin?

1. Anhydrous calcium chloride is used to absorb moisture in the product.

2. Sodium hydroxide is used to absorb and neutralize excess calcium chloride.

3. Paraffin flakes are used to absorb excessive sodium hydroxide.

Therefore, these three steps cannot be reversed, otherwise, the purpose of absorbing water, drying the product and not bringing in other impurities will not be achieved.