Acid–base titrations · 酸碱滴定
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| titration/taɪˈtreɪʃn/ | 滴定 | dī dìng |
| burette/bjʊəˈret/ | 滴定管 | dī dìng guǎn |
| pipette/pɪˈpet/ | 移液管 | yí yè guǎn |
| end point/end pɔɪnt/ | 终点 | zhōng diǎn |
| titre/ˈtɪtə/ | 滴定量 | dī dìng liàng |
Measuring exactly how much
- How do you find the exact concentration of an acid or alkali? With a precise technique called a titration 滴定.
- It finds exactly when an acid and alkali have neutralised each other.
精确测量有多少
- 你如何找到一种酸或碱的确切浓度?用一种叫作滴定(titration)的精密技术。
- 它精确地找到酸和碱何时彼此中和。
In a titration, the piece of apparatus that delivers an exact, measured volume is the: · 在一次滴定中,输送确切的、测量过的体积的那件仪器是:
The burette delivers a precise, variable volume. · 滴定管输送一个精确的、可变的体积。
The apparatus
- A burette 滴定管 delivers an exact, measured volume of one solution.
- A pipette 移液管 measures a fixed volume of the other into a flask.
A titration finds the exact volume of one solution that reacts with another
仪器
- 一个滴定管(burette)输送一种溶液的确切的、测量过的体积。
- 一个移液管(pipette)把另一种的固定体积量入一个烧瓶。
一次滴定找到一种溶液与另一种反应的确切体积
Acid–base titrations · 酸碱滴定
pH jumps at the equivalence point · pH 在等当点跃升
Track the pH as base is added — it leaps through neutral at the equivalence point · 等当点. · 随着碱被加入追踪 pH——它在等当点跃过中性。
The end point of a titration is shown by: · 一次滴定的终点由以下显示:
The indicator changes colour at neutralisation. · 指示剂在中和时改变颜色。
The volume of solution added from the burette is called the . · 从滴定管加入的溶液体积被称为。
The titre is read from the burette. · 滴定量从滴定管读出。
The end point 终点
- An indicator changes colour at the end point — when neutralisation is complete.
- You record the volume of solution added from the burette (the titre 滴定量).
Solution is run from the burette into the flask until the indicator changes colour
终点
- 一种指示剂(indicator)在终点(end point)改变颜色——当中和完成时。
- 你记录从滴定管加入的溶液体积(滴定量,titre)。
溶液从滴定管流入烧瓶,直到指示剂改变颜色
How many moles are in 20 cm³ of acid of concentration 0.5 mol/dm³? (moles = conc × volume in dm³) · 20 cm³ 浓度 0.5 mol/dm³ 的酸中有多少摩尔?(摩尔数 = 浓度 × 以 dm³ 为单位的体积)
0.5 × (20 ÷ 1000) = 0.01 mol. · 0.5 × (20 ÷ 1000) = 0.01 mol。
If 0.01 mol of alkali is in 25 cm³, what is its concentration (mol/dm³)? · 如果 0.01 mol 的碱在 25 cm³ 中,它的浓度(mol/dm³)是多少?
0.01 ÷ (25 ÷ 1000) = 0.4 mol/dm³. · 0.01 ÷ (25 ÷ 1000) = 0.4 mol/dm³。
Using the result
- From the volumes and one known concentration, you calculate the unknown concentration.
- Use moles = concentration × volume and the equation's mole ratio.
Worked example. 25 cm³ of alkali is neutralised by 20 cm³ of acid of concentration 0.5 mol/dm³ (1:1 ratio). Moles of acid = 0.5 × (20 ÷ 1000) = 0.01 mol. So moles of alkali = 0.01, and its concentration = 0.01 ÷ (25 ÷ 1000) = 0.4 mol/dm³.
使用结果
- 从体积和一个已知浓度,你计算未知浓度。
- 使用摩尔数 = 浓度 × 体积和方程的摩尔比。
例题。 25 cm³ 的碱被 20 cm³ 浓度 0.5 mol/dm³ 的酸中和(1:1 比例)。酸的摩尔数 = 0.5 × (20 ÷ 1000) = 0.01 mol。所以碱的摩尔数 = 0.01,而它的浓度 = 0.01 ÷ (25 ÷ 1000) = 0.4 mol/dm³。
You've got it
- a titration finds an unknown concentration by neutralising acid with alkali
- a burette delivers a measured volume; an indicator marks the end point
- calculate using moles = concentration × volume and the mole ratio
你掌握了
- 一次滴定通过用碱中和酸找到一个未知浓度
- 一个滴定管输送一个测量过的体积;一种指示剂标记终点
- 用摩尔数 = 浓度 × 体积和摩尔比计算