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3 years ago

PLEASE ANSWER QUICKLY!! 25. Which gas sample contains a total of 3.0 x 1023 molecules?

Chemistry

1 answer:

nevsk [136]3 years ago

4 0

Answer:

14 g of N2

Explanation:

If we look at the options, we will notice that the correct answer needs to be a gas that has about half of the molecular mass of the gas.

If we consider nitrogen gas whose molecular mass is 28g/mol, half of the molecular mass is 14 g.

So;

28g of N2 contains 6.02 × 10^23 molecules of N2

14g of N2 contains 14 × 6.02 × 10^23 /28

= 3.0 x 10^23

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4 years ago

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In a certain chemical reaction Compound A combines with Compound B to produce Compound C (and no other products). Measurements w

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Answer:

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Actual amount of C isolated = 5.0 g

Explanation:

Given that in the reaction, Compound A combines with Compound B t o produce Compound C and no other products, the reaction is a combination reaction. The equation of the reaction is given below:

A + B ---> C

Part A:

From the measurement of the masses of A and B present before and after the reaction, the following values were obtained:

Initial mass of A = 4.0 g

Final mass of A = 0.0 g

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Part B:

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3 years ago

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3 years ago

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Answer:

The pH of the solution is 9.43

Explanation:

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after removing the spectator ion Na

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since sodium acetate is a weak base, it will not react completely with water. Thus a value "x" will be used to make the products.

At equilibrium:

[CH3COO⁻] = 1.288 - x

[CH3COOH] = x

[H3O⁺] = x

Since a base is reacting with H2O, Kb is used at equilibrium: Kb=(1*10^-14)/(1.8*10^-5) = 5.6*10^-10)

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3 years ago