hòa tan hết 26,5 gam NaCl trong 75 gma H2O ở 20 độ C đc dung dịch X. Cho biết dung dịch Xlaf bão hào hay chưa bão hòa.Giải thích. Biết rằng độ tan của NaCl trong nước ở 20 độ C là 36 gam

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27g co:

Có 36g nacl bão hoà trong 100g h2o

xg nacl bão hoà trong 75g h2o

=>x=(36.75):100= 27g

mà có 26.5g nacl<27g=>dung dịch chưa bão hoà

Đáp án:

Chưa bão hòa

Giải thích các bước giải:

Khi bão hòa, cứ 100g H2O chứa 36g NaCl --

Nếu có 75g H2O thì khi bão hòa sẽ cần 27g NaCl

Mà đb cho 26,5g <27g --> Chưa bão hòa

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