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3 years ago

. How many milliliters of 0.20 M HCl are needed to exactly neutralize 40. milliliters of 0.40 M KOH

Chemistry

1 answer:

Anuta_ua [19.1K]3 years ago

5 0

Answer:

$V_{HCl}=80mL$

Explanation:

Hello,

In this case, for the given reactants we identify the following chemical reaction:

$KOH+HCl\rightarrow KCl+H_2O$

Thus, we evidence a 1:1 molar ratio between KOH and HCl, therefore, for the complete neutralization we have equal number of moles, that in terms of molarities and volumes become:

$n_{HCl}=n_{KOH}\\\\M_{HCl}V_{HCl}=M_{KOH}V_{KOH}$

Hence, we compute the volume of HCl as shown below:

$V_{HCl}=\frac{M_{KOH}V_{KOH}}{M_{HCl}} =\frac{0.40M*40mL}{0.20M} \\\\V_{HCl}=80mL$

Best regards.

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Calculate the standard reaction Gibbs free energy for the following cell reactions: (a) 2 Ce41(aq) 1 3 I2(aq) S 2 Ce31(aq) 1 I32

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Answer:

For a: The standard Gibbs free energy of the reaction is -347.4 kJ

For b: The standard Gibbs free energy of the reaction is 746.91 kJ

Explanation:

Relationship between standard Gibbs free energy and standard electrode potential follows:

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The given chemical equation follows:

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We are given:

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For b:

The given chemical equation follows:

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3 years ago

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Help! What did I do wrong??

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calculation

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