Calculate The $\Delta$ H $\degree$ _rxn for the Following Reaction $\Delta$ H $\degree$ _f [SiO₂(s)] = -910

question 60

Multiple Choice

Calculate the $\Delta$ H $\degree$ _rxn for the following reaction. ( $\Delta$ H $\degree$ _f [SiO₂(s) ] = -910.9 kJ/mol; $\Delta$ H $\degree$ _f [SiCl₄(g) ] = -657.0 kJ/mol; $\Delta$ H $\degree$ _f [HCl(g) ] = -92.3 kJ/mol; $\Delta$ H $\degree$ _f [H₂O (g) ] = -241.8 kJ/mol)

• A) -139.5 kJ
• B) -137.4 kJ
• C) -104.4 kJ
• D) 104.4 kJ
• E) 139.5 kJ

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Definitions:

Margin of Safety Ratio

This ratio measures the difference between actual or expected sales and sales at the break-even point, indicating the buffer against a loss.

Dollar Amount

Refers to the value or cost of something expressed in units of currency.

Break-even Point

The level of production or sales at which total revenues equal total expenses, resulting in no net loss or gain.

Variable Costs

Costs that fluctuate in direct relation to the level of production or volume of operations in a business.