1) Answer: A hot pack feels warm when chemicals in it combine.
Explanation: Reactions or process in which heat is released(produced) are known as exothermic reactions or process and those in which the heat is absorbed are known as endothermic reactions or process.
If a beaker feels cools when chemical in it react then it means the chemicals have absorbed the heat energy from its surroundings and so it is an example of an endothermic process.
A hot pack feels warm when chemicals in it combine means the energy is released in the chemical reaction and so it is an example of an exothermic process.
Plants use the sun's energy for photosynthesis which is a process of forming food for the plants. Energy acts as a reactant in this process and so it is an example of endothermic process.
Frying an egg by heating it on a stove is an example of an endothermic process as the heat is required to fry the egg.
So, the only exothermic process is the second one, "A hot pack feels warm when chemicals in it combine."
2) In the given equation, heat is written as a product means the heat is released in the equation and so it is an example of an exothermic reaction.
So, the correct choice is the last one " It is exothermic because energy is released."
It would form a negative ion... it lacks 1 e in its valence shell., it is easier for F to accept an e than to shed all existing 7.
e= electron
Hey there!
The answer is D, Salinity.
Salinity is the concentration of salt in water. Ocean water often has high salinity and this can contribute to things like upwelling and water density- but these all start from salinity.
Hope this helps!
Answer:
Take a look at the attachment below
Explanation:
Take a look at the periodic table. As you can see, Rubidium is the closest element to Cesium, and happens to have the closest boiling point to Cesium, with only a difference of about 30 degrees.
Respectively, you would think that fluorine should have the least similarity to Cesium with respect to it's boiling point, considering it is the farthest away from the element out of the 4 given. This is not an actual rule, there are no fixed trends of boiling points in the periodic table, there are some but overall the trends vary. However in this case fluorine does have the least similarity to Cesium with respect to it's boiling point, a difference of about 1,546.6 degrees.
<em>Hope that helps!</em>
<span>The ester that is formed by combining propanioc acid with isopropyl alcohol, using heat and an acid catalyst is isopropyl propanoate.</span>