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3 years ago

Please help with this chemistry question, image attached.

Chemistry

1 answer:

Alexeev081 [22]3 years ago

7 0

Answer:

a. Sally did not take account the atoms of the compounds, because she only summed Al + O and in the oxide, we have 2 mol of Al and 3 mol of O

b. The conversion factor that Jacob did, was wrong.

Moles must be divided by moles, so they can be cancelled. The correct conversion factor is:

9.45 mol . 102 g / 1 mol = 963.9 g

Explanation:

Al₂O₃ → Aluminum oxide

We determine the molar mass:

Molar mass Al . 2 + Molar mass O . 3

27 g/mol . 2 + 16 g/mol . 3 = 102 g/mol

a. Sally did not take account the atoms of the compounds, because she only summed Al + O and in the oxide, we have 2 mol of Al and 3 mol of O

b. The conversion factor that Jacob did, was wrong.

Moles must be divided by moles, so they can be cancelled. The correct conversion factor is:

9.45 mol . 102 g / 1 mol = 963.9 g

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To calculate the concentration of nitrate ions in the solution, we use the equation:

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Putting values in above equation, we get:

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Calculating the p-function of zinc ions and nitrate ions in the solution:

For zinc ions:

$\text{p-function of }Zn^{2+}\text{ ions}=-\log[Zn^{2+}]$

$\text{p-function of }Zn^{2+}\text{ ions}=-\log(0.0031)\\\\\text{p-function of }Zn^{2+}\text{ ions}=2.51$

For nitrate ions:

$\text{p-function of }NO_3^{-}\text{ ions}=-\log[NO_3^{-}]$

$\text{p-function of }NO_3^{-}\text{ ions}=-\log(0.0073)\\\\\text{p-function of }NO_3^{-}\text{ ions}=2.14$

Hence, the p-function of $Zn^{2+}$ and $NO_3^{-}$ ions are 2.51 and 2.14 respectively.

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