Gas volumes and solutions · 气体体积与溶液
| English | 中文 | Pinyin · 拼音 |
|---|---|---|
| concentration/ˌkɒnsənˈtreɪʃn/ | 浓度 | nóng dù |
| titration/taɪˈtreɪʃn/ | 滴定 | dī dìng |
| solute/ˈsɒljuːt/ | 溶质 | róng zhì |
| burette/bjʊəˈret/ | 滴定管 | dī dìng guǎn |
| significant figures/sɪɡˈnɪfɪkənt ˈfɪɡəz/ | 有效数字 | yǒu xiào shù zì |
Measuring gases and solutions
- Equal volumes of any gases (same conditions) hold equal numbers of molecules.
- One mole of gas takes a fixed volume at r.t.p.
- For solutions, concentration 浓度 links moles to volume.
测量气体和溶液
- 任何气体相同体积(相同条件)容纳相同数目的分子。
- 一摩尔气体在 r.t.p. 占据固定的体积。
- 对溶液,浓度把摩尔数与体积联系起来。
Gas volume lab · 气体体积实验
n = V / 24 dm3 · n = V / 24 dm³
Change gas volume and see moles scale at room conditions. · 改变气体体积，观察在室温条件下摩尔数的缩放情况。
At room temperature and pressure, one mole of any gas occupies about ______ dm³. · 在室温和常压下，一摩尔任何气体约占 ______ dm³。
This is the molar gas volume at rtp (24 dm³ per mole). · 这是 rtp 下的气体摩尔体积（每摩尔 24 dm³）。
Equal volumes of different gases at the same temperature and pressure contain: · 相同温度和压力下，不同气体的等体积含有：
This is Avogadro's law: equal volumes (same conditions) hold equal numbers of molecules, whatever the gas. · 这是阿伏伽德罗定律：等体积（同条件）包含相等数量的分子，无论气体种类如何。
Volumes of gases
- At the same temperature and pressure, equal volumes contain equal numbers of molecules.
- At r.t.p., one mole of any gas occupies $24.0\ \text{dm}^3$:
The mole is the hub: convert to mass, particles, gas volume or solution concentration
气体的体积
- 在相同的温度和压强下,相同体积含有 相同数目的分子。
- 在 r.t.p.,任何气体一摩尔占据 $24.0\ \text{dm}^3$:
摩尔是枢纽:换算到质量、粒子、气体体积或溶液浓度
How many moles are in 48 dm³ of gas at r.t.p.? (1 mole = 24 dm³) · 在 r.t.p. 下，48 dm³ 气体中含有多少摩尔？(1 摩尔 = 24 dm³)
n = V / 24 = 48 / 24 = 2 mol. · n = V / 24 = 48 / 24 = 2 mol。
Concentration and titration 滴定
- Concentration $c$ is the moles of solute 溶质 per $\text{dm}^3$ of solution (units $\dfrac{\text{mol}}{\text{dm}^3}$):
- A titration finds an unknown concentration by reacting it with a solution of known concentration.
A burette 滴定管 delivers a measured volume of a known solution to find an unknown concentration.
浓度和滴定
- 浓度(concentration) $c$ 是每 $\text{dm}^3$ 溶液中溶质的摩尔数(单位 $\dfrac{\text{mol}}{\text{dm}^3}$):
- 滴定(titration) 通过让未知浓度的溶液与已知浓度的溶液反应来求出它。
滴定管把已知溶液的量好的体积送入,以求出未知浓度。
How many moles of solute are in 250 cm³ of a 0.2 mol/dm³ solution? (250 cm³ = 0.25 dm³) · 250 cm³ 浓度为 0.2 mol/dm³ 的溶液中含有多少摩尔溶质？(250 cm³ = 0.25 dm³)
n = c × V = 0.2 × 0.25 = 0.05 mol. · n = c × V = 0.2 × 0.25 = 0.05 mol。
Match each formula or term to what it gives. · 将每个公式或术语与其对应的计算结果匹配。
Gas volume and solution concentration both convert to moles, the hub of every calculation. · 气体体积和溶液浓度都可转换为摩尔数，这是所有计算的枢纽。
A titration is used to: · 滴定用于：
In a titration, a known solution is added until the reaction is complete, revealing the unknown concentration. · 在滴定中，加入已知浓度的溶液直至反应完全，从而揭示未知浓度。
25 cm³ (0.025 dm³) of an acid is exactly neutralised by 0.002 mol of alkali in a 1:1 reaction. What is the acid's concentration in mol/dm³? · 25 cm³ (0.025 dm³) 的酸恰好被 0.002 mol 的碱中和，反应比例为 1:1。求酸的浓度（mol/dm³）？
The acid is also 0.002 mol; c = n / V = 0.002 / 0.025 = 0.08 mol/dm³. · 酸的摩尔数也是 0.002 mol；c = n / V = 0.002 / 0.025 = 0.08 mol/dm³。
Significant figures 有效数字
- Give answers to a sensible number of significant figures — usually match the data.
- Don't write more digits than the data supports, and don't round too early.
有效数字
- 把答案给到合理数目的 有效数字(significant figures)——通常匹配数据。
- 不要写出比数据支持的更多的位数,也不要太早取整。
You've got it
- equal gas volumes (same T, P) = equal numbers of molecules
- at r.t.p. one mole of gas = $24.0\ \text{dm}^3$, so $n = \dfrac{V}{24.0}$
- solutions: $n = c \times V$ ($c$ in $\dfrac{\text{mol}}{\text{dm}^3}$, $V$ in $\text{dm}^3$; $1000\ \text{cm}^3 = 1\ \text{dm}^3$)
- a titration finds an unknown concentration; quote a sensible number of significant figures
你掌握了
- 相同气体体积(相同 T、P)= 相同数目的分子
- 在 r.t.p. 一摩尔气体 = $24.0\ \text{dm}^3$,所以 $n = \dfrac{V}{24.0}$
- 溶液:$n = c \times V$($c$ 单位 $\dfrac{\text{mol}}{\text{dm}^3}$,$V$ 单位 $\text{dm}^3$;$1000\ \text{cm}^3 = 1\ \text{dm}^3$)
- 滴定 求出未知浓度;给出合理数目的 有效数字