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Colt1911 [192]
3 years ago
8

Select all of the following statements that are basic assumptions of the Bohr model of the atom. Atoms have a central nucleus wi

th electrons in orbit about this nucleus. Atoms are made of positive material with electrons fixed in place in this positive material. Electrons can jump from one orbit to another around the nucleus. They must gain energy to jump to a higher level, and they release energy when jumping to a lower level. Electrons orbit the nucleus, but the orbits can have only certain sizes and energy values. Atoms are solid spheres of matter.
Chemistry
1 answer:
Alekssandra [29.7K]3 years ago
7 0

Answer:

The assumptions of the Bohr model of the atom are:

- Atoms have a central nucleus with electrons in orbit about this nucleus.

- They must gain energy to jump to a higher level, and they release energy when jumping to a lower level.

- Electrons orbit the nucleus, but the orbits can have only certain sizes and energy values.

Explanation:

The Bohr model of the atom establishes that atoms have a central nucleus with positive charge and electrons (with a negative charge) in orbit about this nucleus. In the Bohr model, electrons move in specific orbits with a certain amount of energy and can't jump from one orbit to another around the nucleus. To jump to a higher level, they must gain energy or release energy when jumping to a lower level.

The Thomson model of the atom postulated that <em>atoms are solid spheres of matter</em> and <em>are made of positive material with electrons fixed in place in this positive material</em>.

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Which of the following would not be considered an observation in terms of the scientific method?
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the first option, tasting a pasta sauce after adding a new ingredient.

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: An unknown metal crystallizes in the cubic crystal structure. The metal has a radius 140pm, atomic mass of 135 g/mol, and dens
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The cubic unit cell  this metal crystallize as is BCC structure .

<h3> What is unit cell ?</h3>

The structure of a crystalline solid, whether a metal or not, is best described by considering its simplest repeating unit, which is referred to as its unit cell.

The unit cell consists of lattice points that represent the locations of atoms or ions.

The entire structure then consists of this unit cell repeating in three dimensions

\rm \rho =\dfrac{nM}{N_{0} a^{3}} \\\\\\\\\rm n =\dfrac{\rho N_{0} a^{3}}{M} \\\\\\\\Assuming\; it \; to \; be \; a\; BCC\; structure \\\\\\ r = \dfrac{\sqrt{3} \times a}{4} \\\\\\Therefore\; a = 3.23 \times 10^{-8}\\\\\\\\\rm n =\dfrac{13.3 \times 6.022 \times 10^{23}\times 3.23^{3}\times (10^{-8})^{3}}{135} \\\\

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It is a BCC structure .

Therefore the cubic unit cell  this metal crystallize as is BCC structure .

To know more about unit cell

brainly.com/question/13110055

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2 years ago
A solution of acetic acid has a pH of 3.45. What is the concentration of acetic acid in this solution? Ka for CH3COOH is 1.8×10-
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Answer:

0.007 M

Explanation:

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pH = - log [H⁺]

The expression of the pH of the calculation of weak acid is:-

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Where, C is the concentration = ?

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