Values of heats of formation for \[Si{{O}_{2}}\]and \[MgO\] are \[-48.4\] and \[-34.7\,kJ\] respectively. The heat of the reaction \[2Mg+Si{{O}_{2}}\to 2MgO+Si\] is [KCET 1990]

Values of heats of formation for \[Si{{O}_{2}}\]and \[MgO\] are \[-48.

1.	Values of heats of formation for \[Si{{O}_{2}}\]and \[MgO\] are \[-48.4\] and \[-34.7\,kJ\] respectively. The heat of the reaction \[2Mg+Si{{O}_{2}}\to 2MgO+Si\] is [KCET 1990]
A.	\[21.16\,kJ\]
B.	\[-21.10\,kJ\]
C.	\[-13.62\,kJ\]
D.	\[13.6\,kJ\]
Answer» C. \[-13.62\,kJ\]

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Values of heats of formation for \[Si{{O}_{2}}\]and \[MgO\] are \[-48.4\] and \[-34.7\,kJ\] respectively. The heat of the reaction \[2Mg+Si{{O}_{2}}\to 2MgO+Si\] is [KCET 1990]

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