Which of the following is not a homogeneous mixture?
a. mixture in which substances are evenly mixed on the atomic level but not bonded together
b. solution
c. air
d. mixture in which you can see the different substances with unaided eyes

D. as such mixtures are called suspensions here u can easily see the substances floating aroundthis is heterogenous ( opposite to homogeneous )
examples are sand and water mixture where you can see by practically trying it that the sand will rise inside water and move around but after a while the sand will settle at bottomthese mixtures are not homogeneous

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