D. A mixture
If the water is evaporating while the salt remains, it means the two are not chemically bonded and therefore are not a compound.
A molecule that can h-bond will not always necessarily and does not have guarantee to have a higher boiling point than one than cannot have h-bond.
we can take an example of Pentan-2-one that cannot h-bond but instead of this it has a high boiling point that is 102.3 °C, while propan-1-ol can h-bond but it has a boiling point of 97.2°C, that is lower than the boiling point of Pentan-2-one.
so basically
some fuels have an impurity in them which is sulfur.
When the fuel undergoes combustion, the sulfur reacts with oxygen in the air to form sulfur dioxide.
the sulfur dioxide reacts with water vapour in the air to form sulfurous acid, which is a type of acid rain.
Also
the high pressures inside a car engine may cause nitrogen and oxygen in the air to react and form oxides of nitrogen. the most common compounds formed inside car engines are NO (nitrogen oxide) and NO2 (nitrogen dioxide)
Answer: released to; absorbed from
- In an exothermic reaction, energy is released to the surroundings.
- In an endothermic reaction, energy is absorbed from the surroundings.
Explanation:
An exothermic reaction is a chemical reaction that occurs spontaneously and brings about the release of energy to the surroundings. Hence, the reacting vessel feels hot as the reaction proceeds.
An endothermic reaction, on the other hand, does not occur spontaneously and proceed only when energy is absorbed from the surroundings. Hence, the reacting vessel feels cold as the reaction proceeds.
