解答---**Textual Information Extraction:**
**Question Stem:**
6. 用如图所示装置，分别对燃烧条件和 CO₂ 与水反应的实验进行研究。下列说法中正确的个数为 ( )
**Table Content:**
| 内容 | [实验 1]研究燃烧条件 | [实验 2]研究 CO₂ 与水反应 |
| :------------------------------------- | :------------------------------------------------------------------------------------------------------------------ | :----------------------------------------------------------------------------- |
| 步骤 | ①打开弹簧夹, 通入一段时间 N₂, 关闭弹簧夹, 加热木炭。 | ①向 B 中放入一朵用紫色石蕊溶液浸泡后干燥的纸花。 |
| | ②停止加热, 冷却后打开弹簧夹, 通入 O₂。 | ②打开弹簧夹, 通入 O₂。 |
| | ③______。 | |
| | ④停止通 O₂, 熄灭酒精灯。 | |
*Note: The list of statements referred to in the question stem ("下列说法") is not present in the image.*
*Note: Step ③ in Experiment 1 is a fill-in-the-blank.*
*Note: Experiment 2, Step ② involves passing O₂ according to the table text, which seems inconsistent with the experiment title "研究 CO₂ 与水反应" if the diagram is used for CO₂ production.*
**Chart/Diagram Description:**
* **Type:** Laboratory experimental setup diagram.
* **Main Elements:**
* A horizontal combustion tube (labeled A) containing charcoal (木炭), supported by stands.
* An alcohol lamp heating the combustion tube from below.
* A gas inlet on the left side of the combustion tube controlled by a spring clip (弹簧夹).
* A gas outlet on the right side of the combustion tube connected via tubing to a gas washing bottle (labeled B).
* Gas washing bottle B is connected via tubing to a second gas washing bottle (labeled C).
* Bottle C has a gas outlet tube.
* **Relative Position and Direction:** The setup is arranged linearly from left to right, representing the flow path of gas through the heated tube and then through bottles B and C. The alcohol lamp is positioned directly underneath the combustion tube.