4 _ A ,cuz X is ionic so is solube in water and is the filterate while Y is organic so solube in organic solvents and is in the filterate too
15 _ A , cuz when 5g of X REACT WID 1000 cm , 500cm only react while the excess 500 are used to warm the mixture so when 500cm of water only react wid 5g then then all the 500cm react and there is no excess to warm the mixture and raise the temperature so the the decrease will be double
37 _ C cuz an acid will react with the carbonate to give bubbles of CO2
hope this helps
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