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dissolves completely, but if we add sand in water, it will not dissolve and will settle at the
                    bottom when left undisturbed for some time. Thus, we note that some substances are
                    soluble (dissolve completely) and some are insoluble (that do not dissolve).

                    Soluble substances are those substances that dissolve completely in water or any other
                    solvent to form a solution. Sugar, salt, coff ee, turmeric powder and soap are some solid

                    substances that are soluble in water.







                                                                                           mix


                              salt                  sugar              soap powder                  solutes dissolve
                                                                                                  completely in water
                                                              Soluble solutes

                    Milk and alcohol are liquids that dissolve in water, and when
                    two liquids dissolve completely, they are called miscible liquids.             Did You Know!
                                                                                                     Lemonade is a
                    For example, milk and water are miscible liquids.
                                                                                                   solution of water,
                    Some gases like oxygen, carbon dioxide and chlorine dissolve                    lemon juice and
                    in water. Carbonated drinks are the best examples which show                         sugar.

                    the solubility of gases in water.

                    Insoluble substances are those substances that do not dissolve in water or any other
                    solvent. Sand, stone, fl our, wax and chalk powder are some substances that do not

                    dissolve in water.







                                                                                        mix



                           sand                  stone              chalk powder           solutes do not dissolve in water,
                                                                                              and settle at the bottom
                                                              Insoluble solutes

                    Some liquids do not dissolve completely when mixed together. Such liquids are called
                    immiscible liquids. When immiscible liquids are mixed, the lighter liquid fl oats on the
                    heavier liquid. For example, if we mix oil with water, we can see a distinct layer of oil
                    fl oating on the surface of water, as it is lighter than water.

                    Some gases like hydrogen, nitrogen and helium are insoluble in water.



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