Vectors include magnitude & direction so the third option is the correct answer :)
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: 780 kcal are required to produce 12.00 mol of
Explanation:
Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and written along with reactants.
The balanced chemical reaction is:
According to stoichiometry :
2 moles of are produced by absorption of energy = 130 kcal
Thus 12.00 moles of are produced by absorption of energy =
Thus 780 kcal are required to produce 12.00 mol of
probably none becuase it going staright unless its going down a hill
Answer:
Explanation:
I assume the volume is 2.50 L. A volume of 25.0 L gives an impossible answer.
We have two conditions:
(1) Mass of glucose + mass of sucrose = 1.10 g
(2) Osmotic pressure of glucose + osmotic pressure of sucrose = 3.78 atm
Let g = mass of glucose
and s = mass of sucrose. Then
g/180.16 = moles of glucose, and
s/342.30 = moles of sucrose. Also,
g/(180.16×2.50) = g/450.4 = molar concentration of glucose. and
s/(342.30×2.50) = s/855.8 = molar concentration of sucrose.
1. Set up the osmotic pressure condition
Π = cRT, so
Now we can write the two simultaneous equations and solve for the masses.
2. Calculate the masses
We have 0.229 g of glucose and 0.871 g of sucrose.
3. Calculate the mass percent of sucrose