Answer:
The correct options include choice 2, 3, and 6.
Explanation:
Density is identified as the mass of a substance per unit volume occupied by that substance.

The density remains constant for a given substance, regardless of variations in mass and volume hence it is considered an intensive property.
2. 20.2 g of silver in 21.6 mL of water and 12.0 g of silver also in 21.6 mL of water.
3. 15.2 g of copper in 21.6 mL of water and 50.0 g of copper in 23.4 mL of water.
6. 11.2 g of gold in 21.6 mL of water and 14.9 g of gold in 23.4 mL of water.
The same metals in both instances will yield consistent densities due to the fixed density of the metal.
In a water molecule, the sharing of electrons occurs between the oxygen and hydrogen atoms within covalent bonds; however, this sharing is unequal. The oxygen atom holds a stronger pull on the electrons compared to the hydrogen atoms in the bond.
The ozonolysis of 2,4,4-trimethyl-2-pentene produces a combination of

and

Explanation: In ozonolysis (where a reducing agent like Zn is involved during hydrolysis), a pi bond cleaves to generate ketones or aldehydes.
Ketones arise from the double bond's disubstituted side, whereas aldehydes come from the monosubstituted side of the same bond.
Notably, ozonolysis comprises two steps: (1) the formation of an ozonide, followed by (2) the hydrolysis of the ozonide.
Hydrolysis can transpire with or without a reducing agent. When it occurs without a reducing agent, carboxylic acid, carbon dioxide, or ketones can be produced.
In this case, 2,4,4-trimethyl-2-pentene yields a mixture of
and 
The reaction process is illustrated below.
The correct answer is Option A.
The calculation goes as follows:
Number of millimoles of Na3PO4 = 1 × 100 = 100
Number of millimoles of AgNO3 = 1 × 100 = 100
Dissociating 1 mole of Na3PO4 yields 3 moles of sodium ions and 1 mole of phosphate ions, whereas 1 mole of AgNO3 releases 1 mole of Ag+ and 1 mole of NO3-.
The Ag+ ion concentration becomes negligible since it forms a precipitate with the phosphate ion, indicating that the concentration of phosphate ions is also low.
With 100 millimoles of Na3PO4, we get 300 millimoles of Na+ and 100 millimoles of PO43-, and with 100 millimoles of AgNO3 we have 100 millimoles of Ag+ and 100 millimoles of NO3-.
Thus, the order of increasing concentration is: PO43- < NO3- < Na+.