What is mole in chemistry?

Consider a transition of the electron in the hydrogen atom from n=3 to n=7.

kow [346]

Answer:

For a: The wavelength of light is $1.005\times 10^{-6}m$

For b: The light is getting absorbed

Explanation:

For a:

To calculate the wavelength of light, we use Rydberg's Equation:

$\frac{1}{\lambda}=R_H\left(\frac{1}{n_i^2}-\frac{1}{n_f^2} \right )$

Where,

$\lambda$ = Wavelength of radiation

$R_H$ = Rydberg's Constant = $1.097\times 10^7m^{-1}$

$n_f$ = Higher energy level = 7

$n_i$ = Lower energy level = 3

Putting the values in above equation, we get:

$\frac{1}{\lambda }=1.097\times 10^7m^{-1}\left(\frac{1}{3^2}-\frac{1}{7^2} \right )\\\\\lambda =1.005\times 10^{-6}m$

Hence, the wavelength of light is $1.005\times 10^{-6}m$

For b:

There are two ways in which electrons can transition between energy levels:

Absorption spectra: This type of spectra is seen when an electron jumps from lower energy level to higher energy level. In this process, energy is absorbed.
Emission spectra: This type of spectra is seen when an electron jumps from higher energy level to lower energy level. In this process, energy is released in the form of photons.

As, the electron jumps from lower energy level to higher energy level. The wavelength is getting absorbed.

6 0

4 years ago

Explain why an insoluble compound added to water is considered a nonelectrolyte.

DaniilM [7]

Explanation:

A non-electrolyte is defined as a solution which does not contain any ions and hence, it is unable to conduct electricity.

For example, when a non-polar substance like $CCl_{4}$ is dissolved in water then it will not dissociate into ions.

As electricity is the flow of ions or electrons. So, a non-electrolyte solution is not able to conduct electricity.

Similarly, a compound that is insoluble in water will not dissociate into ions. Hence, this type of solution will not be able to conduct electricity.

8 0

3 years ago

Despite not knowing mechanistic details of the adsorption of water onto silica gel, from the information provided, you should be

navik [9.2K]

Answer:

G<0, spontanteous

H<0, from equation

S>0, gas to solid

Explanation:

The small bags of silica gel you often see in a new shoe box are placed there to control humidity. Despite its name, silica gel is a solid. It is a chemically inert, highly porous, amorphous form of SiO2. Water vapor readily adsorbs onto the surface of silica gel, so it acts as a desiccant. Despite not knowing mechanistic details of the adsorption of water onto silica gel, from the information provided, you should be able to make an educated guess about the thermodynamic characteristics of the process. Predict the signs of ΔG, ΔH, and ΔS.

G<0, spontanteous

H<0, from equation

S>0, gas to solid

8 0

3 years ago

It is found that a gas undergoes a first-order decomposition reaction. If the rate constant for this reaction is 8.1 x 10-2 /min

kap26 [50]

Answer:

28.43 min

Explanation:

Using integrated rate law for first order kinetics as:

$[A_t]=[A_0]e^{-kt}$

Where,

$[A_t]$ is the concentration at time t

$[A_0]$ is the initial concentration

Given that:

The rate constant, k = $8.1\times 10^{-2}$ min⁻¹

Initial concentration $[A_0]$ = 0.1 M

Final concentration $[A_t]$ = $1.0\times 10^{-2}$ M

Time = ?

Applying in the above equation, we get that:-

$1.0\times 10^{-2}=0.1e^{-8.1\times 10^{-2}\times t}$

$0.1e^{-8.1\times \:10^{-2}t}=10^{-2}$

$e^{-8.1\times \:10^{-2}t}=\frac{1}{10}$

$\ln \left(e^{-8.1\times \:10^{-2}t}\right)=\ln \left(\frac{1}{10}\right)$

$t=28.43\ min$

3 0

4 years ago

Balance each skeleton reaction, use Appendix D to calculate E°cell , and state whether the reaction is spontaneous:(a) Cu⁺(aq) +

melamori03 [73]

The balanced equation reaction :

2Cu+(aq) + PbO2(s) + SO42–(aq) + 4H+ -----------> PbSO4(s) + 2 Cu2+(aq) + 2H2O

A balanced equation is an equation for a chemical reaction in which the range of atoms for every detail in the reaction and the full charge is identical for both the reactants and the products. In other phrases, the mass and the fee are balanced in each aspect of the reaction.

A balanced equation happens while the variety of the atoms involved inside the reactants side is identical to the variety of atoms in the goods facet. in this chemical reaction, nitrogen (N2) reacts with hydrogen (H) to provide ammonia (NH3). The reactants are nitrogen and hydrogen, and the product is ammonia.

A chemical equation is the symbolic representation of a chemical reaction inside the form of symbols and formulae, wherein the reactant entities are given on the left-hand side and the product entities.

Eo = Eored - Eo oxd

= 1.69 - 0.153

= 1.54 V

Eocell is positive so the reaction is spontaneous.

Learn more about the balanced reaction here brainly.com/question/15355912

#SPJ4

4 0

2 years ago