Are sand and water a heterogeneous or homogeneous

Salt is soluble in water, which would give a homogeneous mixture. But, when you add sand, which is insoluble, you will have a mixture of two different phases, a solid and a liquid, therefore this is a heterogenous mixture.

Explanation:

Sand and water  heterogenous mixtures

Explanation:

Source Socratic Chmistry mixtures

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

since electrons are negative the answer is neagtaive