Answer:
ΔH = -55.73 kJ/mol
Explanation:
Since the density of water is 1 g/ml and the problem wants us to use this value to find the mass of NaOH and HNO3 we arrange the original equation of
Since no heat was lost or gained
qrxn+qsoln=0. ----> qrxn=-qsoln.
qsol = mc*()
The mass of the solution is the mass of NaOh and HNO3. 100+100= 200.
You plug in the remaining numbers using 4.18 as the heat capacity and 2 as the change in temperature:
qsol=200*(4.18)*(2)= 1672 J
qrxn= -1672 J
Now ΔH = qrxn over the amount in moles or grams. This problem asks for NaOH in moles. To calculate this we use the concentration formula
M= . -----> n=V*M.
Note that you must convert 100 ml to L to use this equation. So we have
n=0.1*0.300 where n=0.03
ΔH =
ΔH = -55733.3 J/mol
ΔH = -55.73 kJ/mol
<u>Answer</u>:
This describes primary succession.
<u>Explanation</u>:
In the case of primary succession, the sequence of communities is formed in lifeless habitat. With the formation of the new ecosystem, life evolves gradually. In retreating glacier’s case, the new land is being revealed on its receding.
During the initial stage, the land is void of soil and vegetation. This leads to micro-organisms to breakdown the bedrock and soil formation starts. With the efficient amount of soil creation the new vegetation starts.
Answer:
The potential energy of both toy vehicles (purple and pink) decreased. Since the pink toy was moved closer to the magnet, it will have less potential energy because of the short distance it will take to travel to the magnet. Although the purple toy is now closer to the magnet, it is still pretty far and will have a somewhat big potential energy when traveling to the magnet.
Explanation:
Hey, I'm in middle school and I had the same question for a science test, I'm not sure if I am correct but this is what I have.
Answer:
216.52°C
Explanation:
Hi, in this problem we know the total heat transfer is 1000 W.
We need to do know is the surface temperature of the iron.
So we are going to use the equation for radiation heat transfer.
So, we have the next data
A = 0.02 m^2
ε= 0.4
h = 20 W/m2·°C
T_∞ = 20°C.
We can assume that the air temperature is Tsurfaces = 20°C = 293.15 K. The Stefan-Boltzmann constant, σ = 5.670x10-8 W/m^2·K^4.
Remember that we have to use Kelvin temperatures for the convection term
489.674K⇒216.52°C