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aleksklad [387]
2 years ago
13

Can someone help me ??????????????????????????????????????????

Chemistry
1 answer:
Lilit [14]2 years ago
7 0

Answer:

              Lithium-7

Explanation:

                    By carefully inspecting the diagram we can see three different sub-particles.

                   1)  Electrons (-vely charged, outside the nucleus)

                   2) Protons (+vely charged, Inside nucleus)

                   3) Neutrons (uncharged, Inside nucleus)

Mass Number:

                       Mass number is the number of protons and neutrons present in the nucleus of an atom.

                    Therefore, in our problem there are 4 neutrons and 3 protons.

So, the mass number is 7.

Atomic Number:

                      Atomic number is the number of protons present in the nucleus. This number shows the identity of an atom. If you go through the periodic table you will find that the atomic number 3 is for Lithium.

Result:

          Lithium-7

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Answer:

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Explanation:

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3 years ago
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Answer:

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the answer to your question is

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3 0
3 years ago
In the decomposition potassium nitride, 10.65 g of nitrogen form. How much potassium nitride was present initially ?
leonid [27]

Answer:

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Explanation:

Given data:

Mass of potassium nitride = ?

Mass of nitrogen produced = 10.65 g

Solution:

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Moles of nitrogen:

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Now we will compare the moles of nitrogen with potassium nitride.

                        N₂              ;         K₃N

                         1               :            2

                         0.38          :          2×0.38 =0.76

Mass of potassium nitride:

Mass = molar mass × number of moles

Mass =    131.3 g/mol ×   0.76 mol

Mass =  99.8 g    

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4 years ago
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3 years ago
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