How Much Heat Is Involved if 927 Grams of Mg(OH)2 Reacts?

AI Thread Summary
The discussion focuses on calculating the heat involved when 927 grams of Mg(OH)2 reacts, using the provided reaction equation. The calculation performed suggests that 70,482 kJ of heat is released based on the molar mass and the heat of reaction. There is uncertainty about the origin of the value 1427 kJ associated with 3 moles of Mg(OH)2, as it was not explicitly stated in the problem. Additionally, there is a query regarding how to properly format chemical symbols in the discussion. The overall concern is ensuring the accuracy of the calculation and clarity in the problem's parameters.
davie08
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Homework Statement


given:

2 H3PO4 + 3 Mg(OH)2 + 1427 kj → 6 H20 + Mg3(PO4)2

How much heat is involved if 927 grams of Mg(OH)2 reacts?


Homework Equations





The Attempt at a Solution



927 g x Mg(OH)2 mole/56.305g x 1427 kj/3Mg(OH)2 mole = 70,482 kj


I just felt like I did this wrong. Also how do I make the numbers small for showing the number of each element?
 
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No idea where 1427 kj/3Mg(OH)2 mole came from - you have not listed it in the problem. It doesn't have to be wrong, it is just not clear if it is OK.

[noparse]H3O+[/noparse] renders as H3O+.
 
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