How Fast a Reaction Goes · 反应速率
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| reaction rate/rɪˈækʃn reɪt/ | 反应速率 | fǎn yìng sù lǜ |
Some changes race, some crawl
- An explosion finishes in a flash; iron rusts over years.
- The same chemistry can run at wildly different speeds.
- We can measure exactly how quickly reactants turn into products.
- A few knobs let us speed things up or slow them down.
有的变化飞奔,有的爬行
- 爆炸一瞬间就结束;铁生锈要好几年。
- 同样的化学可以以千差万别的速度进行。
- 我们能精确测量反应物变成产物有多快。
- 几个旋钮让我们加快或减慢它。
What the rate means
- The reaction rate 反应速率 is how fast concentration changes over time.
- It is measured as concentration used or made per second.
- Reactants fall while products rise.
速率的含义
- 反应速率是浓度随时间变化的快慢。
- 它以每秒消耗或生成的浓度来度量。
- 反应物下降,产物上升。
Reaction rate is usually measured in units of concentration per ____. · 反应速率通常以单位时间内的浓度变化来衡量。
Rate is a change in concentration per unit time, e.g. M/s. · 速率是单位时间内浓度的变化，例如 M/s。
What speeds it up
- Higher concentration means more frequent collisions, so a faster rate.
- Higher temperature means faster, harder collisions, so a much faster rate.
- More surface area and a catalyst also speed it up.
什么让它加快
- 浓度更高意味着碰撞更频繁,所以速率更快。
- 温度更高意味着碰撞更快更猛,所以速率快得多。
- 更大的表面积和催化剂也让它加快。
Raising the temperature generally makes a reaction... · 升高温度通常会使反应...
Hotter particles collide more often and harder, speeding the reaction. · 高温粒子碰撞更频繁且更猛烈，从而加速反应。
Select all · 所有 factors that increase reaction rate. · 选择 所有 能增加反应速率的因素。
Concentration, temperature, and a catalyst all speed the reaction. · 浓度、温度和催化剂都能加快反应。
A catalyst is used up during the reaction it speeds up. · 催化剂在其催化的反应中被消耗。
A catalyst speeds a reaction without being consumed. · 催化剂在不被消耗的情况下加速反应。
Watching it happen
- Track a reactant's concentration as it drops over time.
- The steeper the curve, the faster the rate.
- The rate is largest at the start and slows as reactants run low.
观察它发生
- 跟踪某反应物的浓度随时间下降。
- 曲线越陡,速率越快。
- 速率在开始时最大,随反应物变少而减慢。
Speed up the reaction · 加快反应速度
See how temperature, concentration and a catalyst change how often particles collide and react. · 观察温度、浓度和催化剂如何改变粒子碰撞和反应的频率。
A reaction generally slows down as it proceeds. · 随着反应进行，反应通常会减慢。
Reactants deplete, so collisions become less frequent. · 反应物消耗，导致碰撞频率降低。
A reactant falls from $1.0\ \text{M}$ to $0.8\ \text{M}$ in $10\ \text{s}$. What is the average rate?
- Rate $=$ change $/$ time $= (1.0 - 0.8) / 10$.
- Rate $= 0.02\ \text{M/s}$.
某反应物在 $10\ \text{s}$ 内从 $1.0\ \text{M}$ 降到 $0.8\ \text{M}$。平均速率是多少?
- 速率 $=$ 变化 $/$ 时间 $= (1.0 - 0.8) / 10$。
- 速率 $= 0.02\ \text{M/s}$。
A reactant drops from $0.9\ \text{M}$ to · 到 $0.6\ \text{M}$ in · 入 $5\ \text{s}$. The average rate (in M/s)? · 反应物从 $0.9\ \text{M}$ 降至 $0.6\ \text{M}$ 耗时 $5\ \text{s}$。平均速率（M/s）是多少？
Rate · 速率 $= (0.9 - 0.6)/5 = 0.06\ \text{M/s}$. · 速率 $= (0.9 - 0.6)/5 = 0.06\ \text{M/s}$。
The rate usually slows as the reaction proceeds -- reactants get used up, so collisions grow rarer. Temperature has an outsized effect: a small rise can double the rate. And a catalyst speeds a reaction without being consumed.
速率通常随反应进行而减慢——反应物被耗尽,碰撞越来越少。温度的影响格外大:小小的升温就能让速率翻倍。而且催化剂加快反应而不被消耗。
The reaction rate is how fast concentration changes over time, with reactants falling and products rising. It rises with concentration, temperature, surface area, and a catalyst. The rate is fastest at the start and slows as reactants run out.
反应速率是浓度随时间变化的快慢,反应物下降、产物上升。它随浓度、温度、表面积和催化剂而增大。速率在开始时最快,随反应物耗尽而减慢。