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Ahat [919]
3 years ago
14

An undergraduate weighed out 20grams of sodium hydroxide pellets. If Na =23, O = 16 andH = 1, What is the mole of this sodium hy

droxide.
Chemistry
1 answer:
tatuchka [14]3 years ago
3 0
The answer would be .5 mols because you take the total amount of grams, which is 20, and you had up the molar mass of sodium hydroxide, which would be 40. After you have this you would set this up as a stochiometry equation. With 1 mol on top you dived 20/40 to cancel out your grams. This leaves you with .5 mols

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Answer:

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Explanation:

Based on the given information, the ionic compound is,  

XCl₂ ⇔ X₂⁺ + 2Cl⁻

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As mentioned in the given question, the number of electrons of the element X is 36 and as seen from the reaction the charge present on the ion is +2. Now the atomic number will be,  

No. of electrons = atomic number - charge

36 = atomic number - 2

Atomic number = 38

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= 51 neutrons.  

4 0
3 years ago
1. A gas expands and does p-v work on the surroundings equal to
azamat

The change in energy of the system : -63 J

<h3>Further explanation</h3>

Given

279 J work

216 J heat

Required

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Solution

Laws of thermodynamics 1

ΔU=Q+W

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