Bubbles of hydrogen in electrolysis collect at the ................. while oxygen collects at......................

Answer

To answer the question regarding where hydrogen and oxygen collect during the electrolysis of water, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Electrolysis**: Electrolysis is a chemical process that uses electricity to break down a compound into its elements. In this case, we are looking at the electrolysis of water (H₂O).

2. **Identify the Electrodes**: In electrolysis, there are two electrodes: the anode and the cathode. The anode is the positive electrode, and the cathode is the negative electrode.

3. **Reactions at the Cathode**: At the cathode, reduction occurs. In the case of water electrolysis, water molecules gain electrons (from the cathode) and are converted into hydrogen gas (H₂) and hydroxide ions (OH⁻). Therefore, hydrogen gas bubbles will collect at the cathode.

4. **Reactions at the Anode**: At the anode, oxidation occurs. Water molecules lose electrons (to the anode) and are converted into oxygen gas (O₂) and hydrogen ions (H⁺). Thus, oxygen gas bubbles will collect at the anode.

5. **Fill in the Blanks**: Based on the reactions:
- Bubbles of hydrogen in electrolysis collect at the **cathode**.
- Oxygen collects at the **anode**.

### Final Answer:
Bubbles of hydrogen in electrolysis collect at the **cathode** while oxygen collects at the **anode**.

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