In order to become a scientific theory the three
categories that it must pass are the following:
1) Can the phenomena be recreated in a laboratory setting?
2) Can variables be changed, yet still result in like observations?
3) Is the phenomena truly natural or was it the result of a man-made force
enacting upon it?
Since the density of water is 1 g /mL, hence there is 100
g of H2O. So total mass is:
m = 100 g + 5 g = 105 g
=> The heat of reaction can be calculated using the
formula:
δhrxn = m C ΔT
where m is mass, C is heap capacity and ΔT is change in
temperature = negative since there is a decrease
δhrxn = 105 g * 4.18 J/g°C * (-2.30°C)
δhrxn = -1,009.47 J
=> However this is still in units of J, so calculate
the number of moles of NaCl.
moles NaCl = 5 g / (58.44 g / mol)
moles NaCl = 0.0856 mol
=> So the heat of reaction per mole is:
δhrxn = -1,009.47 J / 0.0856 mol
δhrxn = -11,798.69 J/mol = -11.8 kJ/mol
The
Earth is composed of four different layers. Many geologists believe
that as the Earth cooled the heavier, denser materials sank to the
center and the lighter materials rose to the top. Because of this, the
crust is made of the lightest materials (rock- basalts and granites) and
the core consists of heavy metals (nickel and iron).
<span>The crust is the layer that you live on, and it is the most widely studied and understood. The mantle
is much hotter and has the ability to flow. The Outer and Inner Cores
are hotter still with pressures so great that you would be squeezed into
a ball smaller than a marble if you were able to go to the center of
the Earth!!!!!!</span>
Answer:
Electrons in a hydrogen atom must be in one of the allowed energy levels. If an electron is in the first energy level, it must have exactly -13.6 eV of energy.
...
Energy Levels of Electrons.
Energy Level Energy
1 -13.6 eV
2 -3.4 eV
3 -1.51 eV
4 -.85 eV