Bohr suggested, that there are definitive shells of particular energy and angular momentum in which an electron can revolve. It was not in Rutherford's model
Answer:
Hypothesis is an assumption or idea about a particular topic or argument. An hypothesis should be one which is able to be tested and measurable to determine its authenticity.
A theory is an explanation of a scientific observation which has undergone series of experiments and is reproducible in any part of the world.
A law is simply a rule which gives an in depth explanation of a scientific finding. If new findings emerge the law could be changed or modified.
Answers and Explanation:
a)- The chemical equation for the corresponden equilibrium of Ka1 is:
2. HNO2(aq)⇌H+(aq)+NO−2
Because Ka1 correspond to a dissociation equilibrium. Nitrous acid (HNO₂) losses a proton (H⁺) and gives the monovalent anion NO₂⁻.
b)- The relation between Ka and the free energy change (ΔG) is given by the following equation:
ΔG= ΔGº + RT ln Q
Where T is the temperature (T= 25ºc= 298 K) and R is the gases constant (8.314 J/K.mol)
At the equilibrium: ΔG=0 and Q= Ka. So, we can calculate ΔGº by introducing the value of Ka:
⇒ 0 = ΔGº + RT ln Ka
ΔGº= - RT ln Ka
ΔGº= -8.314 J/K.mol x 298 K x ln (4.5 10⁻⁴)
ΔGº= 19092.8 J/mol
c)- According to the previous demonstation, at equilibrium ΔG= 0.
d)- In a non-equilibrium condition, we have Q which is calculated with the concentrations of products and reactions in a non equilibrium state:
ΔG= ΔGº + RT ln Q
Q= ((H⁺) (NO₂⁻))/(HNO₂)
Q= ( (5.9 10⁻² M) x (6.7 10⁻⁴ M) ) / (0.21 M)
Q= 1.88 10⁻⁴
We know that ΔGº= 19092.8 J/mol, so:
ΔG= ΔGº + RT ln Q
ΔG= 19092.8 J/mol + (8.314 J/K.mol x 298 K x ln (1.88 10⁻⁴)
ΔG= -2162.4 J/mol
Notice that ΔG<0, so the process is spontaneous in that direction.
1. The answer is; C
The geosphere is made up of the physical rocks (composed of metals and minerals) and magma in the different layers. These densities of these rocks surpass those of other spheres such as the atmosphere and hydrosphere.
2. The answer is; B
Destructive forces break down land. Weathering and erosion are categorized as slow destructive forces because they take many years for their effect to be perceptible to the human's scale. Quick destructive forces are forces such as earthquakes and tsunamis.
3. The answer is; B
The atmosphere on earth is mainly composed of molecular nitrogen at 78%. Oxygen takes up 21% and other gases found in the atmosphere are hydrogen, carbon dioxide,ozone, dust, and water vapor at 1%.
4. The answers that apply are ; A & B
The formula for gravity force is given by the equation.; F(gravity) = (G*m1*m2)/d^2 where G is the gravitational constant, m1 and m2 are the masses of the two objects, and d is the distance between them.
5. The answer is; C
The force of inertia is due to their celestial mass. The larger the mass the higher the inertia. Inertia is the tendency of a moving object to maintain a straight path without an external force applied to it. This, therefore, prevents the moon from being pulled into collision with the earth. Gravity, on the other hand, prevents the moon from flying out of its orbit and away into space.
The number of moles of sodium dichromate from the number of moles of oxygen atoms can be determined through stoichiometry. Using the molecular formula of the compound, Na2Cr2O7, 1 mole of the compound contains 7 moles of oxygen. Hence, 14 moles O2*(1 mole Na2Cr2O7/ 7 mole O2) is equal to 2 moles <span>Na2Cr2O7.</span>
