What causes hurricane on Saturn?
1 answer:
You might be interested in
Answer:
Explanation:
A physical change occurs when only the physical properties change. They are generally reversible and no new substances are formed.
However, in a chemical change, the chemical structures and properties change, plus new substances are formed.
Let's analyze each answer choice.
1. Change in state of matter
The state of matter is a physical property, so this is a physical change.
2. Precipitate was formed
A precipitate is a solid formed in a liquid solution. This is a new substance and a chemical change.
3. Unexpected change in odor.
A change in odor is a sign of chemical change.
4. Formation of bubbles
Bubbles signify the formation of gas or a new substance.
So, the best answer choice is <u>A. change in state of matter</u>
The question is incomplete. Complete question is attached below:
...............................................................................................................................
Correct Answer: Option A i.e Flammability
Reason:
Hydrochloric acid is a strong acid. It has a high value of dissociation constant. Following equilibrium is established with HCl is dissolved in water
HCl + H2O ↔ Cl- + H3O+
Above, reaction is highly exothermic in nature. So care must be taken while preparing HCl solution of desired concentration. HCl must be added in beaker containing water. Reversed, i.e. adding water in HCl, must never be done. This is because when acid is poured into water, it flows down the flask and mixes much efficiently and no boiling occurs. On other hand, <span> when water is added to acid, the very first drop of water will react with acid. The heat generated during this event might be high enough to boil the water instantly, which could spray acid out of the container.
The physical contact with concentration HCl will result in skin burn. As well, inhaling</span><span> HCl vapors can cause burns to body tissues, lung damage and even death in extreme cases. Also, since HCl is a strong acid, it would undergoes reaction almost spontaneously, which would inturn favour substitution reaction. However, HCl is not a flammable gas. Hence, it is of no concern while performing substitution reaction. </span>
...............................................................................................................................
Correct Answer: Option A i.e Flammability
Reason:
Hydrochloric acid is a strong acid. It has a high value of dissociation constant. Following equilibrium is established with HCl is dissolved in water
HCl + H2O ↔ Cl- + H3O+
Above, reaction is highly exothermic in nature. So care must be taken while preparing HCl solution of desired concentration. HCl must be added in beaker containing water. Reversed, i.e. adding water in HCl, must never be done. This is because when acid is poured into water, it flows down the flask and mixes much efficiently and no boiling occurs. On other hand, <span> when water is added to acid, the very first drop of water will react with acid. The heat generated during this event might be high enough to boil the water instantly, which could spray acid out of the container.
The physical contact with concentration HCl will result in skin burn. As well, inhaling</span><span> HCl vapors can cause burns to body tissues, lung damage and even death in extreme cases. Also, since HCl is a strong acid, it would undergoes reaction almost spontaneously, which would inturn favour substitution reaction. However, HCl is not a flammable gas. Hence, it is of no concern while performing substitution reaction. </span>