posted by josh on .
I cannot figure out this answer. It is confusing me a lot. I hate problems like this where all of the problems just switch beginnings and endings with each other.
The combination of the sand and water makes for a ____________ _____________ because
A) homogenous mixture; it separates when left undisturbed.
B) heterogenous mixture; it does not separate when left undisturbed.
C) heterogenous mixture; it separates when left undisturded.
D) homogenous mixture; it does not separate when left undisturbed.
Let's think this out. We know sand does not dissolve in water. And we also know that if we shake it up and let it stand, the sand will settle out. SO,
A MAY be correct since it settles.
B can't be right.
C MAY be correct since it settles.
D can't be right.
Now we need only decide between A and C. What's the difference between homogeneous and heterogeneous (note the correct spelling of those two words). Homogeneous means we can't distinguish between the solute and solvent, heterogeneous means we can. A solution of salt or sugar in water is a homogeneous mixture. Something that doesn't dissolve in water (sand and water) is a heterogeneous mixture and it settles on standing; therefore, I would go with C.