Sam prepares a solution of sodium chloride with a concentration of 8 g/dm³. If he only used 2g of sodium chloride, what volume o

The net ionic equation for the reaction between chromium (III) hydroxide and nitrous acid is:

Cr(OH)₃ (s) + 3H⁺ (aq) ⇒ Cr³⁺ (aq) + 3H₂O (l)

Additional Details

An electrolyte dissociates into ions in solution.

Chemical equations can also be represented with ionic species.

Strong electrolytes (fully ionized) are written as separate ions, whereas weak electrolytes (partially ionized) remain as intact molecules.

In ionic equations, spectator ions are those unchanged by the chemical process—they are present both before and after the reaction.

Removing these spectators results in the net ionic equation.

Gases, solids, and water (H₂O) are written as molecules, without ionization.

Therefore, only dissolved compounds are represented by their ions (aq).

The problem involves chromium (III) hydroxide reacting with nitrous acid.

The reaction occurring is:

Cr(OH)₃ (s) + 3HNO₂ (aq) ⇒ Cr(NO₂)₃ (aq) + 3H₂O (l)

Chromium (III) hydroxide is a solid and remains un-ionized, as does water.

Thus, the ionic equation is:

Cr(OH)₃ (s) + 3H⁺ (aq) + 3NO₂⁻ (aq) ⇒ Cr³⁺ (aq) + 3NO₂⁻ (aq) + 3H₂O (l)

The ion 3NO₂⁻ is a spectator ion; removing it yields the net ionic equation:

Cr(OH)₃ (s) + 3H⁺ (aq) ⇒ Cr³⁺ (aq) + 3H₂O (l)

Answer:

A, B, and C

Explanation:

Indeed, atoms possess mass and serve as the fundamental building blocks of chemical elements. While matter is composed of atoms, these particles themselves do not occupy physical space.

Atoms consist mostly of void, which excludes them from the other responses.

This confirms that A, B, and C are the right choices.

The correct answer is C

NOT D

DON'T BE DECEIVED

Answer:

D) Mn + Ni2+ ⇒ Mn2+ + Ni

Explanation:

A spontaneous process can occur in a specific direction without requiring any energy input from external sources. Such reactions happen naturally. In these spontaneous processes, the entropy change is positive (ΔS), the enthalpy change is negative (ΔH), and most importantly, ΔG (the change in free energy) is negative.

To identify which reaction is spontaneous, we analyze the electrode potentials of the involved species. The species with a more negative reduction potential can displace the other from its aqueous solution. In this case, since the reduction potential for Mn^2+ is -1.19 V compared to nickel's -0.25 V, manganese will thus naturally displace Ni^2+ from solution as indicated in the solution above.