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2 years ago

How many electrons are in the n = 2 shell of a magnesium atom?

Chemistry

1 answer:

Montano1993 [528]2 years ago

8 0

Answer:

eight

Explanation:

That means there are 12 electrons in a magnesium atom

hope this helps

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A) The average molecular speed in a sample of Ar gas at a certain temperature is 391 m/s. The average molecular speed in a sampl

diamong [38]

Answer:

For A: The average molecular speed of Ne gas is 553 m/s at the same temperature.

For B: The rate of effusion of $SO_2$ gas is $1.006\times 10^{-3}mol/hr$

Explanation:

For A:

The average molecular speed of the gas is calculated by using the formula:

$V_{gas}=\sqrt{\frac{8RT}{\pi M}}$

$V_{gas}\propto \sqrt{\frac{1}{M}}$

where, M is the molar mass of gas

Forming an equation for the two gases:

$\frac{V_{Ar}}{V_{Ne}}=\sqrt{\frac{M_{Ne}}{M_{Ar}}}$ .....(1)

Given values:

$V_{Ar}=391m/s\\M_{Ar}=40g/mol\\M_{Ne}=20g/mol$

Plugging values in equation 1:

$\frac{391m/s}{V_{Ne}}=\sqrt{\frac{20}{40}}\\\\V_{Ne}=391\times \sqrt{2}=553m/s$

Hence, the average molecular speed of Ne gas is 553 m/s at the same temperature.

For B:

Graham's law states that the rate of diffusion of a gas is inversely proportional to the square root of the molar mass of the gas. The equation for this follows:

$Rate\propto \frac{1}{\sqrt{M}}$

Where, M is the molar mass of the gas

Forming an equation for the two gases:

$\frac{Rate_{SO_2}}{Rate_{Xe}}=\sqrt{\frac{M_{Xe}}{M_{SO_2}}}$ .....(2)

Given values:

$Rate_{Xe}=7.03\times 10^{-4}mol/hr\\M_{Xe}=131g/mol\\M_{SO_2}=64g/mol$

Plugging values in equation 2:

$\frac{Rate_{SO_2}}{7.03\times 10^{-4}}=\sqrt{\frac{131}{64}}\\\\Rate_{SO_2}=7.03\times 10^{-4}\times \sqrt{\frac{131}{64}}\\\\Rate_{SO_2}=1.006\times 10^{-3}mol/hr$

Hence, the rate of effusion of $SO_2$ gas is $1.006\times 10^{-3}mol/hr$

8 0

2 years ago

What are some of the benefits of being able to predict natural disasters and knowing when and where they might occur?

Georgia [21]

So you can know if you have to pack up your belongings and moving somewhere else

7 0

1 year ago

Which of the following is an example of a longitudinal wave?

Genrish500 [490]

An example of a longitudinal wave would be the first option:

"A wave traveling down a stretched Slinky toy, with both ends held

fixed"

<h3>What is a longitudinal wave?</h3>

A longitudinal wave is a wave that oscillates in the same direction that the wave moves.

For example, the option D would not be a longitudinal wave, as the wave travels along the string direction, but the oscillations would be up and down, so this is a transversal wave.

Similarly with option C, water waves, where you can see how the waves expand radially with peaks and throughs, but again, the peaks and throughs are perpendicular to the motion direction, so again this is not a longitudinal wave (the same thing happens with the wave on the surface of a drum, only that here the patterns may be a lot more complex).

Finally, the correct option is A.

The oscillations on a spring are back and forth, so the oscillations are in the same directions than the wave motion, thus, these are longitudinal waves.

If you want to learn more about waves, you can read:

brainly.com/question/15531840

8 0

2 years ago

What describes density?

castortr0y [4]

Answer:

Density is a measure of mass per volume. The average density of an object equals its total mass divided by its total volume. An object made from a comparatively dense material (such as iron) will have less volume than an object of equal mass made from some less dense substance (such as water).

Explanat

3 0

2 years ago

Read 2 more answers

How many moles does 21. 7 L of gas at STP represent?

Oduvanchick [21]

Answer:

.96875 moles

Explanation:

22.4 liters per mole at STP for a gas

21.7 / 22.4 = .96875 moles

3 0

1 year ago