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."
Answer is: <span>the molarity of HCl is </span>0.097 M.
Chemical reaction: LiOH + HCl → LiCl + H₂O.
V(HCl) = 13.60 mL - 1.25 mL = 12.35 mL.
V(LiOH) = 11.20 mL - 2.65 mL = 8.55 mL.
c(LiOH) = 0.140 M.
From chemical reaction: n(LiOH) : n(HCl) = 1 : 1.
c(HCl) · V(HCl) = c(LiOH) · V(LiOH).
c(HCl) = 8.55 mL · 0.140 M / 12.35 mL.
c(LiOH) = 0.097 M.
The film which you called it is photographic film and it is strip like sheet and it's surface is clrear and transparent plastic which is coated on
two sided one side is with gelatin emulsion consists microscopic small light-sensor which is actually very sensitive in nature silver halides crystals. The size shape and other characters of the crystals gives the sensitivity,contrast of different colors combination ,and resolution of the films.
The answer is to test a piece of untreated and treated under same conditions!
I believe sam's response is correct.
When human is riding a moving target with constant speed over a period of time, we tend to have a visual acceleration perception due to our optical movement.
This make people such as Carrie believes that the carousel horses are accelerating while it actually stayed at constant pace.