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3 years ago

Sr 32.8 g, Si 5.2 g and O 11.9 g empirical formula number 11

Chemistry

1 answer:

horsena [70]3 years ago

8 0

$\boxed{\begin{array}{c|c|c|c|c}\boxed{\sf Element}&\boxed{\sf Mass\:in\: compound}&\boxed{\sf No\:of\:moles}&\boxed{\sf Ratio}&\boxed{\sf Simplified\:ratio}\\ \sf Sr &\sf 32.8g &\sf \dfrac{32.8}{87}=0.37&\sf \dfrac{0.37}{0.18}=2.05&\sf 2 \\ \sf Si &\sf 5.2g &\sf \dfrac{5.2}{28}=0.18 &\sf \dfrac{0.18}{0.18}=1&\sf 1\\ \sf O&\sf 11.9g &\sf \dfrac{11.9}{16}=0.74&\sf\dfrac{0.74}{0.18}=4.1 &\sf 4\end{array}}$

Empirical formula:-

$\\ \sf\longmapsto SiSr_2O_4$

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To know the number of atoms, it will be necessary to use the formula of avogadro. We calculate the number of moles then we can calculate the number of avogadro.

The molar mass of:

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3 years ago

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3 years ago

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Answer:

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The root-mean-square speed measures the average speed of particles in a gas, and is given by the following formula:

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where R is molar gas constant = 8.3145 J/K.mol, T is temperature in kelvin, M is molar mass of gas in Kg/mol

For argon, M = 40/1000 Kg/mol = 0.04 Kg/mol, T = 4T , R = R

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For hydrogen; M = 1/1000 Kg/mol = 0.001 Kg/mol, T = T, R = R

Vrms = √(3 * R *T)/0.001 = √3000RT

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4 years ago

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Answer:

The change in entropy in the system is -231.5 J/K

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Step 1: Data given

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Step 2: Calculate the entropy change of vaporization

The entropy change of vaporization = molar enthalpy of vaporization of ethanol / temperature

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The change in entropy in the system is -231.5 J/K

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