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3 years ago

What is the amount of gold present in 15.5g of a pure gold ring? (Au=197)

Chemistry

1 answer:

romanna [79]3 years ago

8 0

Answer:

.0787 moles

Explanation:

I'm assuming you mean moles of gold present as the "amount."

This is a moles to moles calculation, so we set it up as such:

*Note that 15.5g Au is given to us, and 197 g / mol of Au is gold's molar mass.

15.5g Au * (1 mol Au / 197 g Au) = ?

We can evaluate the equation to get 15.5 / 197 to get .0787 moles of Au.

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Answer:

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4 years ago

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Mmm, you can work this one out in your head by reversing it.
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4 years ago

What is the total number of moles (n) of electrons exchanged between the oxidizing agent and the reducing agent in the overall r

Sergeu [11.5K]

Answer:
5 moles of electrons

Explanation:

The balance equation is as follow,

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3 years ago

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Vera_Pavlovna [14]

Answer:

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Explanation:

Hello,

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$Ba^{2+}(aq)+2Cl^-(aq)\rightarrow BaCl_2(aq)$

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Best regards.

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3 years ago

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3 years ago

What is the amount of gold present in 15.5g of a pure gold ring? (Au=197)​

What is the amount of gold present in 15.5g of a pure gold ring? (Au=197)