Answer:
2
Explanation:
In two reactions energy is released.
1) C₆H₁₂O₆ + 6O₂ → 6H₂O + 6CO₂ + heat
It is cellular respiration reaction.It involves the breakdown of glucose molecule in the presence of oxygen to yield large amount of energy. Water and carbon dioxide are also produced as a byproduct.
Glucose + oxygen → carbon dioxide + water + 38ATP
2) 2H₂ + O₂ → 2H₂O ΔH = -486 kj/mol
The given reaction is formation of water. In this reaction oxygen and hydrogen react to form water and 486 kj/mol is also released.
The reaction in which heat is released is called exothermic reaction.
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
Answer:
yes
Explanation:
math is used constantly to improve one's performance. Achieving the objective of shooting a basketball includes using percentages and angles. By finding the most consistent percentage of shots made while using a certain angle, you can find out which player will score the most baskets.
<span>100 kilo joules
There are several phases that this problem undergoes and the final answer is the sum of all the energy used for each phase.
Phase 1. Heating of solid ethanol until its melting point.
Phase 2. Melting of the ethanol until it's completely liquid.
Phase 3. Heating of the liquid ethanol until it reaches its boiling point.
Phase 4. Boiling the ethanol until it's completely vapor.
To make things more interesting, some of our constant are per gram and some others are per mole. So let's calculate how many moles of ethanol we have.
Atomic weight carbon = 12.0107
Atomic weight hydrogen = 1.00794
Atomic weight oxygen = 15.999
Molar mass ethanol = 2*12.0107 + 6*1.00794 + 15.999 = 46.06804 g/mol
Moles ethanol = 75g / 46.06804 g/mol = 1.628026719 mol
Phase 1. Use the specific heat of solid ethanol and multiply by the number of degrees we need to change by the mass we have. So
0.97 J/g*K * 75 g * (-114c - -120c)
= 0.97 J/g*K * 75 g * 6K
= 436.5 J
Phase 2: Time to melt. Just need the moles and the enthalpy of fusion. So:
1.628026719 mol * 5.02 kJ/mol = 8.172694128 kJ
Phase 3: Heat to boiling. Just like heating to melting, just a different specific heat and temperature
2.3J/g*K * 75g * (78c - -114c)
= 2.3J/g*K * 75g * 192 K
= 33120 J
Phase 4: Boil it to vapor. Need moles and enthalpy of vaporization. So
1.628026719 mol * 38.56 kJ/mol = 62.77671027 kJ
Now let's add them together:
436.5 J + 8.172694128 kJ + 33120 J + 62.77671027 kJ
= 0.4365 kJ + 8.172694128 kJ + 33.120 kJ + 62.77671027 kJ
=104.5059044 kJ
Since the least precise datum we have is 2 significant figures, round the result to 2 significant figures, giving 100 kilo joules.</span>
A physical change is when somebody smashes a computer screen. It's physical because the looks are changing of the computer. Hope this helps!