You are high up in the mountains and boil water to make some tea However, when you drink your tea, it is not as hot as it should be. You try again and again, but the water is just not hot enough to make a hot cup of tea. Which is the best explanation for this result? High in the mountains, the air pressure is significantly less than 1 atm, so the boiling point of water is much lower than at sea level.

The air pressure is significantly less than 1 atm, so the boiling point of water is much lower than at sea level.

Explanation:

This has to do with Gay Lussac's Law (a.k.a pressure law) which in essence means that when pressure goes up, temperature goes up and when pressure decreases, temperature decreases. This is why when the air pressure is signifcantly less than 1 atm (the pressure at sea level), the boiling point of water is much lower than at sea level.

while cooking a piece of 1/2 pound beef steak, a cast iron pan (2.4kg in weight) was heated 260 celsius.

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.