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now use this idea to calculate these wit...

now use this idea to calculate these without pen and paper `4.2-(3.2-2.3)`

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` 4.2-(3.2-2.3) =(4.2-3.2)+2.3 =1+2.3 .nive 3 w =3.3 `
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Knowledge Check

  • Fe _(2 ) O _(3 (s)) + (3)/(2) to (3)/(2) CO _(2 (g)) + 2 Fe _(2 (g)) + 2 Fe _((s)) , Delta H ^(@) =+ 234.1kJ C _((s)) + O _(2(g)) to CO _(2 (g)) , Delta H ^(@)=- 393.5 kJ Use these equations and AH° values to calculate DeltaH^(@) for this reaction: 4Fe (s) + 3 O _(2) (g) to 2Fe _(2) O _(3) (s)

    A
    `-1648.7 kJ`
    B
    `-1255.3 kJ`
    C
    `-1021.2 kJ`
    D
    `-129.4 kJ`

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