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Ratling [72]
3 years ago
13

Which of the following statements is true?

Chemistry
1 answer:
k0ka [10]3 years ago
4 0
The second and first one but if it isn’t 2 choices then 1
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Advantages for building on the green hill
Minchanka [31]
I think that building on a green hill
6 0
3 years ago
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Arrange the following H atom electron transitions in order of decreasing wavelength of the photon absorbed or emitted:
Katyanochek1 [597]

The decreasing order of wavelengths of the photons emitted or absorbed by the H atom is : b → c → a → d

Rydberg's formula :

                                   \frac{1}{\lambda} = R_h (\frac{1}{n_1^2}-\frac{1}{n_2^2} ),

where  λ is the wavelength of the photon emitted or absorbed from an H atom electron transition from n_1 to n_2 and R_h = 109677 is the Rydberg Constant. Here n_1 and  n_2 represents the transitions.

(a) n_1 =2 to n_2 = infinity

            \frac{1}{\lambda} = 109677\times (\frac{1}{2^2}-\frac{1}{\infty^2}  ) = 109677/4     [since 1/infinity = 0] Therefore, \lambda = 4 / 109677 = 0.00003647 m

(b) n_1=4 to  n_2 = 20

           \frac{1}{\lambda} = 109677\times (\frac{1}{4^2}-\frac{1}{20^2}  ) = 6580.62

Therefore,  \lambda = 1 / 6580.62 = 0.000152 m

(c) n_1=3 to  n_2 = 10

          \frac{1}{\lambda} = 109677\times (\frac{1}{3^2}-\frac{1}{10^2}  ) = 11089.56

Therefore,  \lambda = 1 / 11089.56 = 0.00009 m

(d)  n_1=2 to  n_2 = 1

          \frac{1}{\lambda} = 109677\times (\frac{1}{2^2}-\frac{1}{1^2}  ) = - 82257.75

Therefore,  \lambda = 1 /82257.75  = - 0.0000121 m  

[Even though there is a negative sign, the magnitude is only considered because the sign denotes that energy is emitted.]

So the decreasing order of wavelength of the photon absorbed or emitted is b → c → a → d.

Learn more about the Rydberg's formula athttps://brainly.com/question/14649374

#SPJ4

8 0
1 year ago
How many grams of CaCl2 are needed to make 277.8g of a solution that is 31.5% (m/m) in water? Note that mass is not technically
Sveta_85 [38]

<u>Answer:</u> The mass of calcium chloride present in given amount of solution is 87.5 g

<u>Explanation:</u>

We are given:

Mass of solution = 277.8 grams

Also, 31.5 % (m/m) of calcium chloride in water. This means that 31.5 g of calcium chloride is present in 100 g of solution.

To calculate the mass of calcium chloride in the given amount of solution, we use unitary method:

in 100 g of solution, the mass of calcium chloride present is 31.5 g

So, 277.8 g of solution, the mass of calcium chloride present is \frac{31.5}{100}\times 277.8=87.5g

Hence, the mass of calcium chloride present in given amount of solution is 87.5 g

8 0
3 years ago
Which event may occur when ocean salinity increases?
Vladimir [108]
It’s d like 100000000% trust me
4 1
3 years ago
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Can some help me do this we have a final tomorrow and i have now idea how to do it. Step by Step explanation and tips If you kno
Romashka-Z-Leto [24]

Answer:

87.27 grams

Explanation:

The mole ratio of nitrogen to hydrogen is 1:3; while that one of hydrogen to the products (ammonia) is 3:2

Thus if 3 moles of hydrogen gas produce 2 moles of ammonia gas

7.7 moles of hydrogen will produce:

(7.7moles×2)/3

77/15 moles

1 mole of ammonia gas has a mass of  14+3=17

since the mass of an atom of nitrogen is 14 while that of hydrogen atom is 1.

Therefore 77/15 moles will have a mass of

77/15 moles × 17=87.27 grams

3 0
3 years ago
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