Hello Noor Ul Ain ,

Your copper nitrate trihydrate is a deliquescent salt, which means that it will absorb water from the atmosphere and eventually liquify. The only way to slow down this process is to store the bottle containing the salt in a sealed desiccator backfilled with dry nitrogen gas. Every time you take out and open the bottle to use some of the salt, you should backfill the bottle with dry nitrogen gas before you screw the bottle lid back on and place the sealed bottle back in the desiccator, which you refill with dry nitrogen gas.

Note, you must place a desiccant such as silica gel or CaCl2 in the bottom of the desiccator.

Regards,

Tom Cuff

Thomas Cuff Thank you for your kind advice.

Copper nitrate salt should be stored in a cool, dry, and well-ventilated area, away from sources of heat and direct sunlight. It should be stored in a tightly sealed container, such as a glass or plastic bottle, to prevent moisture from entering and reacting with the salt.

Alireza Badiei I have kept the copper nitrate salt bottle in cool dry place and away from light. But it has lost its crystal structure after 4-5 years of use. It has become liquid paste type. I am unable to use it in my experiments. Is there any way to restore the crystal structure of the salt?

It is possible that the copper nitrate salt has absorbed moisture from the air, causing it to dissolve and lose its crystal structure over time. Unfortunately, once a salt has lost its crystal structure, it cannot be easily restored.

One thing you can try is to heat the copper nitrate salt gently in a clean and dry container to see if it will recrystallize. However, this method is not guaranteed to work and can be dangerous if not done properly.

Another option is to purchase a new bottle of copper nitrate salt. It is important to ensure proper storage of the new bottle to prevent it from experiencing the same issue in the future. You can consider using a desiccator or other methods to reduce humidity and prevent moisture absorption.

Additionally, it may be worth examining your laboratory conditions to see if there are any factors contributing to the loss of crystal structure in your chemical samples. Ensuring proper storage conditions and minimizing exposure to light, air, and moisture can help extend the lifespan and usability of your chemicals.