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3 years ago

Physical sciencePLEASE HELP ME

Chemistry

1 answer:

kondaur [170]3 years ago

5 0

Answer:

The answer to your question is:

Explanation:

Mass number is the sum of protons and neutrons if an atom.

Protons and neutrons in the atom. This is true is the definition of mass number.

Neutrons and electrons in the atom. It's false, if we sum the number of neutrons and electrons, the result could be the same as the mass number but it's not the definition of mass number.

Protons in the atom. Incorrect, if only consider protons that is atomic number not mass number.

Electrons in the atom. Incorrect, mass number doesn't consider electrons in its definition.

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How do disease causing organism reach from one organism to other

Anon25 [30]

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Infectious diseases are commonly transmitted through direct person-to-person contact.

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3 years ago

The majority of Canada’s manufacturing takes place in the provinces of Ontario and __________.

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C. Quebec hope this helps :)

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3 years ago

Read 2 more answers

Given the wavelength of the corresponding emission line, calculate the equivalent radiated energy from n = 4 to n = 2 in both jo

lions [1.4K]

Explanation:

It is given that,

Initial orbit of electrons, $n_i=4$

Final orbit of electrons, $n_f=2$

We need to find energy, wavelength and frequency of the wave.

When atom make transition from one orbit to another, the energy of wave is given by :

$E=-13.6(\dfrac{1}{n_f^2}-\dfrac{1}{n_i^2})$

Putting all the values we get :

$E=-13.6(\dfrac{1}{(4)^2}-\dfrac{1}{(2)^2})\\\\E=2.55\ eV$

We know that : $1\ eV=1.6\times 10^{-19}\ J$

So,

$E=2.55\times 1.6\times 10^{-19}\\\\E=4.08\times 10^{-19}\ J$

Energy of wave in terms of frequency is given by :

$E=hf$

$f=\dfrac{E}{h}\\\\f=\dfrac{4.08\times 10^{-19}}{6.63\times 10^{-34}}\\\\f=6.14\times 10^{14}\ Hz$

Also, $c=f\lambda$

$\lambda$ is wavelength

So,

$\lambda=\dfrac{c}{f}\\\\\lambda=\dfrac{3\times 10^8}{6.14\times 10^{14}}\\\\\lambda=4.88\times 10^{-7}\ m\\\\\lambda=488\ nm$

Hence, this is the required solution.

4 0

3 years ago

The empirical formula for trichloroisocyanuric acid, the active ingredient in many household bleaches is OCNCI. The molar mass o

TEA [102]

Answer:

These two are equivalent and valid:

$C_3Cl_3N_3O_3$

$Cl_3(CN)_3O_3$

Explanation:

The molecular superscripts for each atom in the molecular formula are determined by the number of times that the mass of the empirical formula is contained in the molar mass.

1. Determine the mass of the empirical formula:

$OCNCl$ :

Atomic masses:

O: 15.999g/mol
C: 12.011g/mol
N: 14.007g/mol
Cl: 35.453g/mol

Total mass:

15.999g/mol + 12.011g/mol + 14.007g/mol + 35.453g/mol = 77.470g/mol

2. Divide the molar mass by the mass of the empirical formula:

232.41g/mol / 77.470g/mol = 3

3. Multiply each superscript of the empirical formula by the previous quotient: 3

$O_3C_3N__3Cl_3$

Or:

$C_3Cl_3N_3O_3$

You might also write CN as a group:

$Cl_3(CN)_3O_3$

8 0

3 years ago

Please help me with chemistry

jok3333 [9.3K]

I will, I am in a chemistry class right now. What’s up?

8 0

3 years ago

*Physical science*PLEASE HELP ME

Physical sciencePLEASE HELP ME