Answer:
Rust is a chemical reaction (oxidation) of iron that occurs over a period of time as the bare metal surface comes in contact with oxygen present in the air or water. Rust "eats" away the metal, rendering it weak and fragile. ... Avoid contact with water or moisture.
Answer:

Explanation:
We will need a chemical equation with masses and molar masses, so, let's gather all the information in one place.
Mᵣ: 28.01 17.03
N₂ + 3H₂ ⟶ 2NH₃
m/g: 240.0
(a) Moles of NH₃

(b) Moles of N₂

(c) Mass of N₂

Answer:
(C) The recrystallization solvent should be nonvolatile.
Explanation:
Recrystallization is the separation technique which is used to purify the solid compounds in their crystal or amorphous form.
Some properties follow the recrystallization process as:
The solids are more soluble in hot solvent as compared to the solubility in the cold solvent.
The solvent must have lower boiling point and can be volatile easily.
The solvent should not react with the compound.
The impurities must be soluble in the cool solvent, so that only the pure product crystallizes.
Hence, Answer - C which is not an ideal characteristic.
Your question has been heard loud and clear.
Both scientific laws and scientific theories are not based on hypothesis.
Because , scientific laws are proven and so they are real not hypothetical.
Whereas scientifc theories can be hypothetical.
Thank you