Answer:
4.52 x 10¹⁴ cycles/s
Explanation:
From c = f·λ => f = c/λ = (3.0 x 10⁸ m/s)/(6.63 x 10⁻⁷m) = 4.52 x 10¹⁴ cycles/s.
f = frequency = ?
λ = wavelength = 6.63 x 10⁻⁷ meter
c = speed of light in vacuum = 3.0 x 10⁸ meters/s
The volume of the 0.279 M Ca(OH)₂ solution required to neutralize 24.5 mL of 0.390 M H₃PO₄ is 51.4 mL
<h3>Balanced equation </h3>
2H₃PO₄ + 3Ca(OH)₂ —> Ca₃(PO₄)₂ + 6H₂O
From the balanced equation above,
- The mole ratio of the acid, H₃PO₄ (nA) = 2
- The mole ratio of the base, Ca(OH)₂ (nB) = 3
<h3>How to determine the volume of Ca(OH)₂ </h3>
- Molarity of acid, H₃PO₄ (Ma) = 0.390 M
- Volume of acid, H₃PO₄ (Va) = 24.5 mL
- Molarity of base, Ca(OH)₂ (Mb) = 0.279 M
- Volume of base, Ca(OH)₂ (Vb) =?
MaVa / MbVb = nA / nB
(0.39 × 24.5) / (0.279 × Vb) = 2/3
9.555 / (0.279 × Vb) = 2/3
Cross multiply
2 × 0.279 × Vb = 9.555 × 3
0.558 × Vb = 28.665
Divide both side by 0.558
Vb = 28.665 / 0.558
Vb = 51.4 mL
Thus, the volume of the Ca(OH)₂ solution needed is 51.4 mL
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brainly.com/question/14356286
32.063 u is the answer, add all the variables and divide
Answer:
To have the electronic configuration equal to 1s²2s²2p⁶3s²3p⁶4s²3d⁷, the chemical element must have an electrical charge equal to 27, that is, it must have 27 electrons, such as Cobalt (Co), for example.
Explanation:
The electronic configuration shown in the question above is known as the Linus Pauling distribution and represents the energy sub-levels that an electrically charged atom can have in relation to the amount of electrons it has.
The layers sub-levels are presented in the following order 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹º 4p⁶ 5s² 4d¹º 5p⁶ 6s² 4f14 5d¹º 6p⁶ 7s² 5f14 6d¹º 7p⁶. Where the small numbers represent the number of electrons in each sub-level and the large numbers represent the layers of electronic distribution.
Accordingly, we can see that an atom that has the configuration 1s²2s²2p⁶3s²3p⁶4s²3d⁷ has 27 electrons, like Cobalt.
Answer:
The Bohr model show the protons in a carbon atom using the model; "Electrons move in fixed orbits around a nucleus of protons and neutrons."
According to Bohr's model of the atoms, the Rutherford model is basically correct. This implies that Bohr model accepts the idea of a nucleus containing nucleons(protons and neutrons).
In addition, the model also postulates that electrons are found in fixed orbits. These fixed orbits are called energy levels or shells.
A graphic description of this is shown in the image attached to this answer.
Learn more: brainly.com/question/3964366
Explanation:
