Density is a physical property. It's measured and doesn't change the object chemically.
Answer:

The air in the atmosphere consists of nitrogen, oxygen, which is the life-sustaining substance for animals and humans, carbon dioxide, water vapour and small amounts of other elements (argon, neon, etc.). Higher in the atmosphere air also contains ozone, helium and hydrogen.
Answer:
Lesson 3 Quiz ReturntoAssessmentList Part 1 of 4 - 4.0/ 8.0 Points Question 1 of ... in the balloon containing regular air D.Each balloon has an equal number of atoms. ... The purity of those pre-1982 pennies are really about 95% copper (5% zinc ... that had a mass of 3.11 grams, how many atoms of copper would you have?
Explanation:
Answer:
a) If the solvent-solute interactions in a mixture are <u>stronger than</u> the solvent-solvent interactions and the solute-solute interactions, a homogeneous solution forms.
b) If the solvent-solute interactions in a mixture are <u>weaker than</u> the solvent-solvent interactions and the solute-solute interactions, the formation of a homogeneous solution is uncertain.
Explanation:
The solubility of solute in given solvent mainly depends upon the intermolecular interactions between the solvent and the solute. If the solute is surrounded and solvated by the solvent then the solute will dissolve in that solvent. Therefore, in order to dissolve the solute must form stronger interactions with the solvent as compared to the solute solute interactions or solvent solvent interactions.
Example:
When NaCl is added to water the partial negative oxygen of water is attracted to Na⁺ of NaCl and the partial positive hydrogen of water is attracted to Cl⁻ of NaCl. These new interactions between the NaCl ions and water are stronger than the interactions between water molecules and NaCl molecules themselves hence, results in solubility of NaCl in water.
On the other hand, if NaCl is added to Hexane (C₆H₁₄) it fails to make strong interactions with the solvent molecules resulting in insolubility of NaCl in hexane.