English for chemical engineering and petrochemical refining lesson 6 the reaction rate

LESSON 6 – Text 1• One of the most fundamental empirical observations that a chemist can make is how the concentrations of reactants and products vary with time.. • In general, as is tru

ENGLISH FOR CHEMICAL ENGINEERING

AND PETROCHEMICAL - REFINERY

Hoang Anh Viet Dung

December 2016

1

LESSON 5 – Review

Vocabulary

Homogeneous /həʊməʊˈdʒiːniəs/: đồng nhất, đồng thể Phase /feɪz/: pha

Component /kəmˈpəʊnənt/: thành phần, cấu tử

Binary /ˈbaɪnəri/: kép, lưỡng, đôi

Pure /pjʊə(r)/: tinh khiết, thuần khiết

Solvent /ˈsɒlv(ə)nt/: dung môi

Quantity /ˈkwɒntəti/: số lượng

Solute /ˈsɒljuːt/: chất tan

Uniform /ˈjuːnɪfɔː(r)m/: đồng nhất, nhất quán

distinguishable /dɪˈstɪŋɡwɪʃəb(ə)l/: khác biệt

Distinction /dɪˈstɪŋkʃ(ə)n/ sự khác nhau, sự phân biệt

To evaporate /ɪˈvæpəreɪt/ bay hơi, bốc hơi

volatile /ˈvɒlətaɪl/ dễ bay hơi

1 Dung môi là thành phần chiếm số lượng lớn trong một dung dịch

Solvent/ component/ which/present/large/quantity/solution

Solvent is the component which is present a large quantity in a solution.

2 Nếu hai thành phần của dung dịch dễ bay hơi thì sự phân biệt dung dịch và chất tinh khiết không đơn giản.

If/components/a solution/volatile/the distinction/a pure substance/is/simple

If two components of a solution are volatile, the distinction between a pure substance and solution is not simple.

LESSON 5 – Review

LESSON 6 – Text 1

• One of the most fundamental empirical observations that a chemist can make is how the concentrations of reactants and products vary with time The first substantial quantitative study of the rate of a reaction was performed by L Wilhelmy, who in 1850 studied the inversion of sucrose

in acid solution with a polarimeter There are many methods for making such observations: one might monitor the concentrations spectroscopically, through absorption, fluorescence, or light scattering; one might measure concentrations electrochemically, for example, by potentiometric determination of the pH; one might monitor the total volume or pressure if these are related in a simple way to the concentrations Whatever the method, the result is usually something like that illustrated in Figure 2.1

LESSON 6 – Text 1

• In general, as is true in this figure, the reactant concentrations will decrease as time goes on, while the product concentrations will increase There may also be "intermediates" in the reaction, species whose concentrations first grow and then decay with time How can we describe these changes in quantitative mathematical terms?

• We define the rate law for a reaction in terms of the time rate of change

in concentration of one of the reactants or products In general, the rate

of change of the chosen species will be a function of the concentrations

of the reactant and product species as well as of external parameters such as the temperature For example, In Figure 2.1 the rate of change for a species at any time is proportional to the slope of its concentration curve The slope varies with time and generally approaches zero as the reaction approaches equilibrium The stoichiometry of the reaction determines the proportionality constant

LESSON 6 – Text 1

Vocabulary

Fundamental: cơ bản

Chemist: nhà hóa học

Concentration: nồng độ

Substantial: đáng kể, quan trọng

Quantitative: định tính

Rate: tốc độ

To perform: thực hiện

Inversion: sự biến đổi ngược

Sucrose:

Polarimeter: phân cực kế

Spectroscopically: quang phổ

Absorption: hấp thụ

Fluorescence: huỳnh quang

Light scattering: tán xạ ánh sáng

Electrochemically: điện hóa Potentiometric: đo hiệu điện thế

To illustrate: minh họa Intermediate: sản phẩm trung gian Specie: hợp chất, loại, loài

To decay: phân hủy Rate law: định luật tốc độ phản ứng Reactant: chất phản ứng

External: ngoài, ngoại vi Proportional: tỷ lệ

Slope: độ dốc Concentration curve: đường nồng độ

To approach: tiếp cận, tiến tới Equilibrium: cân bằng

Stoichiometry: hệ số tỷ lệ

1 Who performed the first substantial quantitative study of

the reaction’s rate?

L Wilhelmy did.

2 What did L Wilhelmy study?

He studied the inversion of sucrose in acid solution with a polarimeter.

3 What is one of the most fundamental empirical

observations that a chemist can do?

It is how the concentration of reactants and products vary with time.

4 From the Figure 2.1, what will increase when time goes

on?

The product concentration will increase.

Exercise 1: questions

LESSON 6 – Text 1

5 From the Figure 2.1, what will decrease when time goes

on?

The reactant concentration will decrease

6 How do we define the rate law for a reaction?

In term of the time rate of change in concentration of one of the reactants or products.

7 What is the rate of change of specie proportional to?

It is proportional to the slope of its concentration curve.

8 What does the stoichiometry of the reaction determine?

It determines the proportionality constant.

Exercise 1: questions

LESSON 6 – Text 1

1 Tốc độ của phản ứng hóa học phụ thuộc vào thành phần của chất tham gia phản ứng và rất nhiều yếu tố khác

Reaction/ rate/ depend/composition/reactant/factor

The reaction’s rate depends on the composition of the reactants and other factors.

2 Nồng độ chất phản ứng giảm theo thời gian.

The/concentration/reactant/decrease/as/time/go

The reactant concentration will decrease as time goes on.

Exercise 2: translate into English

LESSON 6 – Text 1

Lesson 6: Grammar Giving definitions

11

A generator is a machine A generator changes mechanical energy into electrical energy.

A generator is a machine which/that changes

mechanical energy into electrical energy.

Relative pronouns

That or which replaces the subject when it is a thing

or an animal

That or who replaces the subject when it is a person Where replaces the subject when it is a place

Lesson 6: Grammar Giving definitions

12

1 Sara is a lead engineer She works on an oil rig.

Sara is a lead engineer who/that works on an oil rig

2 A drain is a device It allows water to leave a tank

A drain is a device which/that allows water to leave a

tank

3 This is the trainer He teaches English for the oil and gas industry.

This is the trainer who/that teaches English for the

oil and gas industry.

Lesson 6: Homework

13

- Read and translate into Vietnamese text 1