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liberstina [14]
3 years ago
5

A Se ion has a mass number of 79 and a charge of − 2 . Determine the number of neutrons, protons, and electrons in this ion.

Chemistry
1 answer:
posledela3 years ago
8 0

Answer:

45, 34, 36

Explanation:

The atomic number of Selenium is 34 and the atomic number is 79 also the atom has gained two electron denoted by superscript -2

number of neutrons = mass number - atomic number = 79 - 34 = 45

number of proton = atomic number = 34

number of electron = 34 + 2 = 36. In an atom the number of proton is always equal to number of electron if the atom is neutral but this Se atom has gain two so the number of electron will exceed the number of proton by 2.

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3 years ago
How many moles are in sample containing 2.71 x 10^24 atoms of iron?
Deffense [45]

Answer:

4.5 moles

Explanation:

One mole is equal to 6.022 x 10^23 atoms

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3 years ago
What is the concentration of a solution with a volume of 660L that contains 33.4g of AlCO3?
lana [24]

Answer:

The concentration of the solution is 5.8168 × 10^{-4} mol.dm^{-3}

Explanation:

Here, we want to calculate the concentration of the solution.

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The number of moles = mass/molar mass

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x moles will be present in 1 dm^3

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4 0
3 years ago
Read 2 more answers
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Yuliya22 [10]
Excuse me not giving an explanation; I haven't even learned chemistry before. I usually give explanations for math/english.

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