He Rydberg formula can be extended for use with any hydrogen-like chemical elements.
<span>1/ λ = R*Z^2 [ 1/n1^2 - 1/n2^2] </span>
<span>where </span>
<span>λ is the wavelength of the light emitted in vacuum; </span>
<span>R is the Rydberg constant for this element; R 1.09737x 10^7 m-1 </span>
<span>Z is the atomic number, for He, Z =2; </span>
<span>n1 and n2 are integers such that n1 < n2 </span>
<span>The energy of a He+ 1s orbital is the opposite to the energy needed to ionize the electron that is </span>
<span>taking it from n = 1 (1/n1^2 =1) to n2 = ∞ (1/n2^2 = 0) </span>
<span>.: 1/ λ = R*Z^2 = 1.09737x 10^7*(2)^2 </span>
<span>λ = 2.278*10^-8 m </span>
<span>E = h*c/λ </span>
<span>Planck constant h = 6.626x10^-34 J s </span>
<span>c = speed of light = 2.998 x 10^8 m s-1 </span>
<span>E = (6.626x10^-34*2.998 x 10^8)/(2.278*10^-8) = 8.72*10^-18 J ion-1 </span>
<span>Can convert this value to kJ mol-1: </span>
<span>(8.72*10^-18*6.022 x 10^23)/1*10^3 = 5251 kJ mol-1 </span>
<span>Lit value: RP’s secret book: 5240.4 kJ mol-1 (difference is due to a small change in R going from H to He+) </span>
<span>So energy of the 1s e- in He+ = -5251 kJ mol-1</span>
Answer:
59.2 grams
Explanation:
We are given that 70.4% of the weight of the total 200 g of the concentration is made up of nitric acid, the remaining information is not required to solve the problem. Since water and nitric acid are the only components of the solution, the total weight of water is given by:
There are 59.2 grams of water in this solution.
Answer:
The statement that best describes the use of catalytic converters in automobiles is;
They oxidize hydrocarbons to form less toxic gases
Explanation:
Catalytic converters
A working engine produces some air pollutants which are made due to fuel not completely burnt in the engine, including unburnt gasoline (a hydrocarbon), nitrogen oxides, and carbon monoxide
Carbon monoxide is poisonous to breathe in if present in the air around us, and nitrogen oxides causes acid rain and smog, while hydrocarbon from the gasoline causes smog
The catalyst in the catalytic converters aids in the conversion of the harmful gases produced by the car engine into harmless gases such as the types of gases already existing in the atmosphere and therefore, can be released into the air
The catalysts in the catalytic converter work by either oxidizing some of the harmful gases such as the unburnt hydrocarbons, or by reducing the other harmful gases such as the nitrogen oxides.
Therefore, the statement that best describes the use of catalytic converters in automobiles is that they oxidize hydrocarbons to form less toxic gases
When a light is on, it is part of a "closed" circuit.
