Write a balanced half-reaction for the oxidation of chromium ion Cr + 3 to dichromate ion Cr 2 O − 2 7 in basic aqueous solution. Be sure to add physical state symbols where appropriate.

14 OH⁻(aq) + 2 Cr³⁺(aq) = Cr₂O₇²⁻(aq) + 7 H₂O(l) + 6 e⁻

Explanation:

In order to balance a half-reaction we use the ion-electron method.

Step 1: Write the half-reaction

Cr³⁺(aq) = Cr₂O₇²⁻(aq)

Step 2: Perform the mass balance, adding H₂O(l) and OH⁻(aq) where appropriate

14 OH⁻(aq) + 2 Cr³⁺(aq) = Cr₂O₇²⁻(aq) + 7 H₂O(l)

Step 3: Perform the electric balance, adding electrons where appropriate

14 OH⁻(aq) + 2 Cr³⁺(aq) = Cr₂O₇²⁻(aq) + 7 H₂O(l) + 6 e⁻

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?