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2 years ago

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The atomic number of nitrogen is 7. nitrogen-15 has a greater mass number than nitrogen-14 because the atomic nucleus of nitroge

n-15 contains _____. 8 neutrons 15 protons 7 neutrons 8 protons

2 answers:

schepotkina [342]2 years ago

7 0

8 neutrons (7 protons)

Paha777 [63]2 years ago

5 0

Answer: Option (a) is the correct answer.

Explanation:

Atomic number means the sum of total number of protons acquired by an atom.

So, when atomic number of nitrogen is 7 then it means there are 7 protons present.

Whereas atomic mass means the sum of total number of protons and neutrons present in an atom.

Therefore, nitrogen-15 is an isotope of nitrogen that will always have 7 protons when it is neutral in nature. Hence, in nitrogen-15 the number of protons and neutrons are calculated as follows.

Atomic mass = no. of protons + no. of neutrons

15 = 7 + no. of neutrons

no. of neutrons = 15 - 7

= 8

Thus, we can conclude that the atomic nucleus of nitrogen-15 contains 8 neutrons.

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we are given

a swimming pool contains 2,850 kiloliters (kL) of water

2,850 kiloliters (kL)=2850000L

we know that

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$3.785L=1gal$

Firstly , we will find for 1L

$1L=\frac{1}{3.785}gal$

now, we can multiply both sides by 2850000

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Answer :

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(c) Now we have to calculate the total heat.

$\Delta H=\frac{q}{n}$

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$q=\Delta H\times n$

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$\Delta H$ = enthalpy change = -187.6 kJ/mol

q = heat = ?

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