Answer: The best way to promote the process are:
--> Add a bit of solid as a seed crystal.
--> Scratch the bottom of the flask gently with a stirring rod.
Explanation:
A crystal growth is seen is SUPERSATURATED solutions which contains more solute than it can normally dissolve at that given temperature. It is usually very UNSTABLE and capable of releasing the excess solute if disturbed, either by shaking or seeding with a tiny crystals.
Crystallization can be used for the separation of two salts with different solubilities as well as for purification of a soluble salt that contains insoluble solid impurities. Recrystallization improves the validity of the process. Crystallization can be initiated by:
--> Scratching the bottom of the flask gently with a stirring rod: scratching initiates crystallization by providing energy from the high-frequency vibrations.
--> Adding a bit of solid as a seed crystal: Seed crystals create a nucleation site where crystals can begin growth.
Answer:
This reaction is exothermic because the system shifted to the left on heating.
Explanation:
2NO₂ (g) ⇌ N₂O₄(g)
Reactant => NO₂ (dark brown in color)
Product => N₂O₄ (colorless)
From the question given above, we were told that when the reaction at equilibrium was moved from room temperature to a higher temperature, the mixture turned dark brown in color.
This simply means that the reaction does not like heat. Hence the reaction is exothermic reaction.
Also, we can see that when the temperature was increased, the reaction turned dark brown in color indicating that the increase in the temperature favors the backward reaction (i.e the equilibrium shift to the left) as NO₂ which is the reactant is dark brown in color. This again indicates that the reaction is exothermic because an increase in the temperature of an exothermic reaction will shift the equilibrium position to the left.
Therefore, we can conclude that:
The reaction is exothermic because the system shifted to the left on heating.
Answer:
Atoms are single neutral particles. Molecules are neutral particles made of two or more atoms bonded together.
Explanation:
Atom refers to the smallest constituent unit of a chemical element. Molecules refer to a group of two or more atoms that are held together due to chemical bonds.
Sugar increases the viscosity of water
hope that helps
Answer:
a single-replacement reaction replaces one element for another in a compound. A double-replacement reaction exchanges the cations, or the anions, of two ionic compounds.