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    a test tube holding the equilibrium system shown below was placed in a beaker of ice and the colour of the solution changed from blue to pink

    [Co(H2O)6]2+ + 4HCl <----> [CoCl4]2- + 6H2O

    pink blue

    On heating, the solution turned blue, using these observation, state whether the forward reaction is exothermic or endothermic,

    I said the answer would be exothermic since the the solution turning pink means the equilibrium position moved to the left

    but the answer is that increasing the temp causes the equilibrium to move to the right; the forward reaction is endothermic.

    so i have obviously misunderstood everything completely wrong

    PLEASE HELP!!!
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    (Original post by BuuTuu)
    a test tube holding the equilibrium system shown below was placed in a beaker of ice and the colour of the solution changed from blue to pink

    [Co(H2O)6]2+ + 4HCl <----> [CoCl4]2- + 6H2O

    pink blue

    On heating, the solution turned blue, using these observation, state whether the forward reaction is exothermic or endothermic,

    I said the answer would be exothermic since the the solution turning pink means the equilibrium position moved to the left

    but the answer is that increasing the temp causes the equilibrium to move to the right; the forward reaction is endothermic.

    so i have obviously misunderstood everything completely wrong

    PLEASE HELP!!!
    It soulds like you have the logic correct, but don't appreciate that endothermic reactions absorb heat energy and proceed more when heated.
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    Yes but if it was an endothermic reaction, on heating shouldn't the solution stay blue as the forward reaction would increase and more CoCl4 would be produced??
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    (Original post by BuuTuu)
    Yes but if it was an endothermic reaction, on heating shouldn't the solution stay blue as the forward reaction would increase and more CoCl4 would be produced??
    Co(aq)2+ ... pink
    [CoCl4]2- ... blue

    If the forward reaction is endothermic than increase of temperature will push the equilibrium towards the products.

    If the products are blue then the pink solution turns blue.
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    Ohhh I read the colours wrongg, I'm so dumb x_x thank you
 
 
 
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