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Please help with Question 1 :How many grams of Na2S will be produced if you react 35.0 g sodiumQuestion 2 Aluminum metal has a specific heat of 0.900 j/g•°c. calculate the amount of heat required to raise the temperature of 10.5 moles of al from 30.5 °c to 225°c. a) 1.84 kjb. 2.41 kjc. 65.1 kjd. 49.6 kje. 57.3 kj

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Answer: 59.41 grams of Na2S

Explanation

Na2S will be formed from the chemical reaction below :


2Na\text{ +S }\Rightarrow\text{ Na}_2S

We are given :

• Mass of Na = 35.0 g rams

,

• Molar mass Na = 22,989769 g/mol

(1) Calculate moles Na


\begin{gathered} Moles\text{ Na =}\frac{Mass\text{ }}{Molecular\text{ mass }} \\ \text{ = }\frac{35\text{ g }}{22.989769g.mol^(-1)} \\ \text{ }\therefore\text{ Moles Na =1.522 moles of Sodium } \end{gathered}

(2) From stoichiometry, the balanced equation informs us that :

2 mole Na will produce 1 mole Na2S

Then , 1.522 moles Na will produce X moles Na2S

Therefore, X moles Na2S = (1.522mole Na * 1 mole Na2S)/ 2 moles Na

=0.761 moles on Na2S will be produced .

(3) Calculate Mass of Na2S

• Molecular mass Na2S = 78,0452 g/mol


\begin{gathered} Mass\text{ Na}_2S\text{ = Molecular mass Na}_2S\text{ * moles Na}_2S \\ \text{ = 78.0452g/mol *0.761 moles } \\ \text{ =59.41 grams } \end{gathered}

This means that 59.41 grams of Na2S will be produced from 35 g Na.

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