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2 years ago

3. In a neutral atom, this element has an atomic mass of 23 AMU and has 11 protons.

Chemistry

1 answer:

notka56 [123]2 years ago

4 0

The element in question is Sodium

An atomic mass unit is defined as 1/12 th of the mass of carbon-12 atom.

The mass of an atom is mainly due to its protons and neutrons in the nucleus.

Weight of a proton is 1.6 x 10^-27 kg

Weight of a neutron is 1.6 x 10^-27kg

However weight of an electron is 9 x 10^-31kg and hence is negligible in calculation of amu

It is given that weight is 23 AMU and number of protons is 11

The protons in a nucleus also act as atomic number of the periodic table

Proton number 11 is the atomic number of Sodium

Hence the element is Sodium

For further reference:

brainly.com/question/13668134?referrer=searchResults

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Here's what I get.

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Thus, if f = 90 THz

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I found an exercise pretty similar to this, so i'm gonna use the data of this exercise to show you how to do it, and then, replace your data in the procedure so you can have an accurate result:

<em>"At a certain temperature the vapor pressure of pure benzene (C6H6) is measured to be 0.63 atm. Suppose a solution is prepared by mixing 79.2 g of benzene and 115. g of heptane (C7H16) Calculate the partial pressure of benzene vapor above this solution. Round your answer to 2 significant digits. Note for advanced students: you may assume the solution is ideal".</em>

<em />

Now, according to the data, we want partial pressure of benzene, so we need to use Raoul's law which is:

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Where:

P: Partial pressure

Xₐ: molar fraction

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Let's determine the moles of each compound:

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To get the molar fractions, we use the following expression:

Xₐ = moles(C₆H₆) / moles in solution

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Finally, the partial pressure is:

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Hope this helps

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