3 years ago

Which of the following may indicate that a chemical reaction has occurred?

Chemistry

1 answer:

lianna [129]3 years ago

3 0

Answer:

D, all of the above

Explanation:

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A particular energy level in the hydrogen atom has E = -2.42 x 10-19 J. Use Bohr's model of the energy levels in hydrogen to cal

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Answer:

n=3

Explanation:

The expression for the energy of an electron for the hydrogen atom in the nth orbit is:-

$E_n=-2.18\times 10^{-18}\times \frac{1}{n^2}\ Joules$

Given that:-

$E_n=-2.42\times 10^{-19}\ Joules$

Applying in the equation to find the value of n as:-

$-2.42\times 10^{-19}=-2.18\times 10^{-18}\times \frac{1}{n^2}$

$n^2=\frac{2.18\times 10^{-18}}{2.42\times 10^{-19}}$

$n=\sqrt{\frac{21.8}{2.42}}=3$

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DaniilM [7]

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because of over-hunting, poaching, pollution, loss of habitat, the arrival of invasive species, and other human-caused problems

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Answer:

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Since..., Density = mass/volume

;Firstly calculate the volume change of the water when the metal is placed in,

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The starting position of this object is m. The object is traveling at a velocity of m/s.

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