When matter changes into new of different substance

Escoge uno de los derechos de la siguiente lista que están Escogidos en el código de la niñez y adolescencia escribe en una hoja

Lera25 [3.4K]

Answer:

Hehe I don't know spanish -

Explanation:

6 0

3 years ago

375 mL of a 0.88 M potassium hydroxide solution is added to 496 mL of a 0.76 M cesium hydroxide solution. Calculate the pOH of t

AysviL [449]

Answer:

pOH of resulting solution is 0.086

Explanation:

KOH and CsOH are monoacidic strong base

Number of moles of $OH^{-}$ in 375 mL of 0.88 M of KOH = $\frac{0.88\times 375}{1000}moles$ = 0.33 moles

Number of moles of $OH^{-}$ in 496 mL of 0.76 M of CsOH = $\frac{0.76\times 496}{1000}moles$ = 0.38 moles

Total volume of mixture = (375 + 496) mL = 871 mL

Total number of moles of $OH^{-}$ in mixture = (0.33 + 0.38) moles = 0.71 moles

So, concentration of $OH^{-}$ in mixture, $[OH^{-}]$ = $\frac{0.71}{871}\times 1000M=0.82M$

Hence, $pOH=-log[OH^{-}]=-log(0.82)=0.086$

8 0

3 years ago

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

3 years ago

The combustion of ammonia in the presence of excess oxygen yields no2 and h2o: 4 nh3 (g) + 7 o2 (g) â 4 no2 (g) + 6 h2o (g) the

VLD [36.1K]

The answer would be 118.68 g.
Explanation for this is:4 moles of NH3 give 4 moles of NO2
so 1mole of NH3 will give 1 mole of NO2
43.9 grams of NH3 contains 2.58 moles
so 2.58 moles will be produced of NO2
which is 118.7 grams this the amount of oxygen that is used.

8 0

3 years ago

Predict what the population of the United States will be in the year 2010

s344n2d4d5 [400]

Answer:

308.7 million

Explanation:

is my prediction

5 0

3 years ago