Answer:
First ionization of lithium:
.
Second ionization of lithium:
.
Explanation:
The ionization energy of an element is the energy required to remove the outermost electron from an atom or ion of the element in gaseous state. (Refer to your textbook for a more precise definition.) Some features of the equation:
- Start with a gaseous atom (for the first ionization energy only) or a gaseous ion. Write the gaseous state symbol
next to any atom or ion in the equation. - The product shall contain one gaseous ion and one electron. The charge on the ion shall be the same as the order of the ionization energy. For the second ionization energy, the ion shall carry a charge of +2.
- Charge shall balance on the two sides of the equation.
First Ionization Energy of Li:
- The products shall contain a gaseous ion with charge +1
as well as an electron 
. - Charge shall balance on the two sides. There's no net charge on the product side. Neither shall there be a charge on the reactant side. The only reactant shall be a lithium atom which is both gaseous and neutral:
.
- Hence the equation:
.
Second Ionization Energy of Li:
- The product shall contain a gaseous ion with charge +2:
as well as an electron . - Charge shall balance on the two sides. What's the net charge on the product side? That shall also be the charge on the reactant side. What will be the reactant?
- The equation for this process is
.
Answer:
1) 0.0025 mol/L.s.
2) 0.0025 mol/L.s.
Explanation:
<em>H₂ + Cl₂ → 2HCl.</em>
<em></em>
<em>The average reaction rate = - Δ[H₂]/Δt = - Δ[Cl₂]/Δt = 1/2 Δ[HCl]/Δt</em>
<em></em>
<em>1. Calculate the average reaction rate expressed in moles H₂ consumed per liter per second.</em>
<em></em>
The average reaction rate expressed in moles H₂ consumed per liter per second = - Δ[H₂]/Δt = - (0.02 M - 0.03 M)/(4.0 s) = 0.0025 mol/L.s.
<em>2. Calculate the average reaction rate expressed in moles CI₂ consumed per liter per second.</em>
<em></em>
The average reaction rate expressed in moles Cl₂ consumed per liter per second = - Δ[Cl₂]/Δt = - (0.04 M - 0.05 M)/(4.0 s) = 0.0025 mol/L.s.
Absorbed photon energy
Ea = hc/λ.. (Planck's equation)
Ea = hc / 92.05^-9m
<span>Energy emitted
Ee = hc/ 1736^-9m </span>
Energy retained ..
∆E = Ea - Ee = hc(1/92.05<span>^-9 - 1/1736^-9) </span>
<span>∆E = (6.625^-34)(3.0^8) (1.028^7)
∆E = 2.04^-18 J </span>
<span>Converting J to eV (1.60^-19 J/eV)
∆E = 2.04^-18 / 1.60^-19
∆E = 12.70 eV </span>
<span>Ground state (n=1) energy for Hydrogen = - 13.60eV </span>
<span>New energy state = (-13.60 + 12.70)eV = -0.85 eV </span>
<span>Energy states for Hydrogen
En = - (13.60 / n²) </span>
n² = -13.60 / -0.85 = 16
n = 4
Answer:
1.72 M
Explanation:
Molarity is the molar concentration of a solution. It can be calculated using the formula a follows:
Molarity = number of moles (n? ÷ volume (V)
According to the information provided in this question, the solution has 58.7 grams of MgCl2 in 359 ml of solution.
Using mole = mass/molar mass
Molar mass of MgCl2 = 24 + 35.5(2)
= 24 + 71
= 95g/mol
mole = 58.7g ÷ 95g/mol
mole = 0.618mol
Volume of solution = 359ml = 359/1000 = 0.359L
Molarity = 0.618mol ÷ 0.359L
Molarity = 1.72 M
