Atoms cannot be created or detroyed, only rearranged.
Answer:
Explanation:
If the energy of an atom is increased, an electron in the atom gets excited. To go back to its ground state, the electron releases energy. The energy of the light released when an electron drops in energy level is the same as the difference in energy between the two levels.
Viewed simply, electrons are arranged in shells around an atom’s nucleus. Electrons closest to the nucleus will have the lowest energy. Electrons further away from the nucleus will have higher energy. An atom’s electron shell can accommodate 2n2 electrons (where n is the shell level).
In a more realistic model, electrons move in atomic orbitals, or subshells. There are four different orbital shapes: s, p, d, and f. Within each shell, the s subshell is at a lower energy than the p. An orbital diagram is used to determine an atom’s electron configuration.
There are guidelines for determining the electron configuration of an atom. An electron will move to the orbital with lowest energy. Each orbital can hold only one electron pair. Electrons will separate as much as possible within a shell.
Answer:
(a) Cu²⁺ +2e⁻ ⇌ Cu
(c) 0.07 V
Explanation:
(a) Cu half-reaction
Cu²⁺ + 2e⁻ ⇌ Cu
(c) Cell voltage
The standard reduction potentials for the half-reactions are+
<u> E°/V
</u>
Cu²⁺ + 2e⁻ ⇌ Cu; 0.34
Hg₂Cl₂ + 2e⁻ ⇌ 2Hg + 2Cl⁻; 0.241
The equation for the cell reaction is
E°/V
Cu²⁺(0.1 mol·L⁻¹) + 2e⁻ ⇌ Cu; 0.34
<u>2Hg + 2Cl⁻ ⇌ Hg₂Cl₂ + 2e⁻; </u> <u>-0.241
</u>
Cu²⁺(0.1 mol·L⁻¹) + 2Hg + 2Cl⁻ ⇌ Cu + Hg₂Cl₂; 0.10
The concentration is not 1 mol·L⁻¹, so we must use the Nernst equation
(ii) Calculations:
T = 25 + 273.15 = 298.15 K
![Q = \dfrac{\text{[Cl}^{-}]^{2}}{ \text{[Cu}^{2+}]} = \dfrac{1}{0.1} = 10\\\\E = 0.10 - \left (\dfrac{8.314 \times 298.15 }{2 \times 96485}\right ) \ln(10)\\\\=0.010 -0.01285 \times 2.3 = 0.10 - 0.03 = \textbf{0.07 V}\\\text{The cell potential is }\large\boxed{\textbf{0.07 V}}](https://tex.z-dn.net/?f=Q%20%3D%20%5Cdfrac%7B%5Ctext%7B%5BCl%7D%5E%7B-%7D%5D%5E%7B2%7D%7D%7B%20%5Ctext%7B%5BCu%7D%5E%7B2%2B%7D%5D%7D%20%3D%20%5Cdfrac%7B1%7D%7B0.1%7D%20%3D%2010%5C%5C%5C%5CE%20%3D%200.10%20-%20%5Cleft%20%28%5Cdfrac%7B8.314%20%5Ctimes%20298.15%20%7D%7B2%20%5Ctimes%2096485%7D%5Cright%20%29%20%5Cln%2810%29%5C%5C%5C%5C%3D0.010%20-0.01285%20%5Ctimes%202.3%20%3D%200.10%20-%200.03%20%3D%20%5Ctextbf%7B0.07%20V%7D%5C%5C%5Ctext%7BThe%20cell%20potential%20is%20%7D%5Clarge%5Cboxed%7B%5Ctextbf%7B0.07%20V%7D%7D)
C to know the background knowledge on how the machine was built can help you identify a potential problem
Answer:
Explanation:
q= mc theta
where,
Q = heat gained
m = mass of the substance = 670g
c = heat capacity of water= 4.1 J/g°C
theta =Change in temperature=(
66-25.7)
Now put all the given values in the above formula, we get the amount of heat needed.
q= mctheta
q=670*4.1*(66-25.7)
=670*4.1*40.3
=110704.1
