Explanation

The blue color of a Cu²⁺ salt solution is due to the transition of electrons within the d-orbitals (from one d orbital to another, i.e., a d-d transition).

Explanation

Aluminum (Al) reacts with oxygen to form a thin protective oxide layer (Al₂O₃) that prevents further oxidation.

This is why it doesn’t react aggressively with oxygen after this initial reaction.

Explanation

Lithium (Li) forms only a normal oxide, Li₂O, when reacting with oxygen.

Other alkali metals (like Na, K) form peroxides and superoxides.

Explanation

The electronegativity of aluminum is 1.5.

The electronegativity of beryllium is 1.5. > The electronegativity of aluminum is similar to the electronegativity of beryllium

Explanation

The standard hydrogen electrode (SHE) is used as a reference electrode with an assigned electrode potential of 0 V.

Explanation

Explanation

Potassium iodide (KI) is a strong electrolyte because it completely dissociates into ions in solution,

unlike weak acids or bases such as acetic acid or ammonium hydroxide.

Explanation

Lattice energy is calculated using the Born-Haber cycle, considering the heat of sublimation, dissociation, ionization, electron affinity, and heat of formation.

After applying the Born-Haber cycle, the lattice energy of KBr is -679.3 kJ/mol.

Explanation

Hess's law states that the total enthalpy change of a reaction is the same, regardless of the number of steps in which the reaction occurs, allowing ∆H to be measured indirectly.

Explanation

To calculate the total energy consumed, you can use the following approximate energy values for macronutrients:

• Carbohydrates: 4 kcal per gram
• Proteins: 4 kcal per gram
• Fats: 9 kcal per gram

Now, let's calculate the energy from each macronutrient: