CO₂与石灰水测试

用氢氧化钙检测二氧化碳

Gas Laws Beginner (Middle School) 20 分钟 ~$5.00

目标

从碳酸盐-酸反应中产生二氧化碳气体，并用石灰水测试确认其存在。

背景

When baking soda (sodium bicarbonate) reacts with vinegar (acetic acid), CO₂ gas is produced. Bubbling this gas through limewater (calcium hydroxide solution) produces a characteristic white milky precipitate of calcium carbonate, confirming the presence of CO₂.

安全警告

  • Limewater is mildly irritating — avoid eye contact
  • CO₂ is an asphyxiant in large quantities — work in ventilated area

所需PPE

goggles

材料

  • Baking soda (NaHCO₃) (10 g)
  • White vinegar (50 mL)
    5% acetic acid
  • Limewater (Ca(OH)₂ solution) (100 mL)
    Clear, saturated

设备

Erlenmeyer flask (250 mL) Rubber stopper with delivery tube Test tubes Rubber tubing

步骤

1

Pour 100 mL of clear limewater into a test tube or small beaker.

2 分钟
2

Place 10 g of baking soda in the Erlenmeyer flask.

1 分钟
3

Add 50 mL of vinegar to the flask. Quickly insert the stopper with delivery tube.

2 分钟 Vigorous effervescence
4

Direct the delivery tube into the limewater. Bubble the CO₂ through for 2-3 minutes.

3 分钟
5

Observe the limewater turning milky white as calcium carbonate precipitate forms.

2 分钟
6

Continue bubbling. If enough CO₂ passes through, the solution may turn clear again as soluble Ca(HCO₃)₂ forms.

5 分钟

预期结果

The clear limewater turns milky white due to CaCO₃ precipitation: Ca(OH)₂ + CO₂ → CaCO₃ + H₂O. With excess CO₂, the milkiness clears: CaCO₃ + CO₂ + H₂O → Ca(HCO₃)₂.

清理

Neutralize remaining vinegar solution. Dispose of limewater down the drain. Rinse all equipment.

详情

类别
Gas Laws
难度
Beginner (Middle School)
时长
20 分钟
预估费用
$5.00
步骤数
6
材料
3

更多实验

扩散速率比较（格雷厄姆定律） 30 min 标准状态下气体的摩尔体积 35 min 气球演示查理定律 30 min 氢气的收集 35 min 玻意耳定律验证 40 min 笛卡尔潜水员 15 min 蒸气压与沸点 45 min 镁的气体化学计量学 40 min

Frequently Asked Questions

What is the objective of CO₂与石灰水测试?
从碳酸盐-酸反应中产生二氧化碳气体，并用石灰水测试确认其存在。
How difficult is CO₂与石灰水测试?
This experiment is rated as Beginner (Middle School). It takes approximately 20 minutes to complete.
What safety precautions are needed for CO₂与石灰水测试?
Key safety precautions include: Limewater is mildly irritating — avoid eye contact; CO₂ is an asphyxiant in large quantities — work in ventilated area.
What materials are needed for CO₂与石灰水测试?
The main materials required are: Baking soda (NaHCO₃), White vinegar, Limewater (Ca(OH)₂ solution).
What results should I expect from CO₂与石灰水测试?
The clear limewater turns milky white due to CaCO₃ precipitation: Ca(OH)₂ + CO₂ → CaCO₃ + H₂O. With excess CO₂, the milkiness clears: CaCO₃ + CO₂ + H₂O → Ca(HCO₃)₂.