<span>Answer:
For this problem, you would need to know the specific heat of water, that is, the amount of energy required to raise the temperature of 1 g of water by 1 degree C. The formula is q = c X m X delta T, where q is the specific heat of water, m is the mass and delta T is the change in temperature. If we look up the specific heat of water, we find it is 4.184 J/(g X degree C). The temperature of the water went up 20 degrees.
4.184 x 713 x 20.0 = 59700 J to 3 significant digits, or 59.7 kJ.
Now, that is the energy to form B2O3 from 1 gram of boron. If we want kJ/mole, we need to do a little more work.
To find the number of moles of Boron contained in 1 gram, we need to know the gram atomic mass of Boron, which is 10.811. Dividing 1 gram of boron by 10.811 gives us .0925 moles of boron. Since it takes 2 moles of boron to make 1 mole B2O3, we would divide the number of moles of boron by two to get the number of moles of B2O3.
.0925/2 = .0462 moles...so you would divide the energy in KJ by the number of moles to get KJ/mole. 59.7/.0462 = 1290 KJ/mole.</span>
Answer:
+125.4 KJmol-1
Explanation:
∆H C4H10(g) = -2877.6kJ/mol
∆H C(s)=-393.5kJ/mol
∆H H2(g) = -285.8
∆H reaction= ∆Hproducts - ∆H reactants
∆H reaction= (-2877.6kJ/mol) - [4(-393.5kJ/mol) +5(-285.8)]
∆H reaction= +125.4 KJmol-1
The study of chemistry helps us understand the nature of the world around us. Chemistry is always developing to keep up with any phenomenon that appears in nature.
Therefore, scientists and chemists are always developing new technologies. However, chemists must very careful when developing these new technologies. They should consider any bad chemical reactions that might occur and also chemicals that harmful to either the individuals or the environment.
P S
4 10
you just use the roots given in the molecular formula
Answer:
D.A high temperature will make it spontaneous.
Explanation:
we know that
Δ G = Δ H - TΔS
For spontaneous reaction
Δ G should be negative . If Δ G = 0
Δ H = TΔS
T = Δ H / Δ S
At temperature above this T , Δ G becomes negative if Δ S and ΔH are positive .
So at a high temperature will make it spontaneous.
