facebook
favorite buttonAdd to Wish List
favorite buttonAdd to Wish List
member icon
Trusted teacher
from172.00SAR/ h

Thermal changes accompanying physical and chemical changes

Translated by Google. Click to view original.
Thermal changes accompanying physical and chemical changes
Thermal changes accompanying physical changes

- melting temperature
It is the temperature change when one mole of solute is dissolved in a given amount of solvent
(The amount of heat energy absorbed or released when one mole of solute is dissolved in a given amount of solvent).
During the dissolution process: two processes occur:
A- Dissociation: the breaking of bonds (endothermic reaction)

Sodium and chloride ions dissociate from the crystal lattice as a result of the ionic bond breaking.
The energy absorbed to break the bond is called the heat of the crystal lattice (bond energy).
- Crystal lattice temperature: It is the energy needed to break the bond between ions in the crystal lattice.

B- Hydration: The dissociated ions bind with water molecules to form hydration ions (exothermic process).

Rehydration temperature:

It is the amount of heat released when hydrating ions bind to water molecules.
If the crystal lattice temperature > heat of hydration

Dilution temperature:
It is the heat change per mole of solute when diluted from a concentrated solution to a dilute solution.
(It is the heat change of one mole of solute when diluted in a large amount of water (about 1000 moles of solvent)).

Sedimentation temperature:
The amount of heat released when one mole of an insoluble substance is completely precipitated.

- heat of combustion
It is the amount of heat released when one mole of a substance is completely burned in an abundance of oxygen. (The reaction is always exothermic).

Formation temperature:
It is the amount of heat released or absorbed when one mole of a compound is formed from its elemental elements so that the elements are in their standard state. (at 25 °C, a pressure of 76 x g).

Note:
Heat of formation of the elements = zero

Location

At student's location: Around Mecca, Saudi Arabia

|
Use ctrl + wheel to zoom!
+

General info

Age:
Teenagers (13-17 years old)
Adults (18-64 years old)
Student level:
Beginner
Intermediate
Advanced
Duration:
60 minutes
The class is taught in:Arabic, English

Ask a question

Send a message explaining your needs and د. وليد will reply soon:
The more detail, the better.
Ex. "Hi, when are you available to meet for a lesson?"

Availability of a typical week

(GMT -05:00) Chicago
MonTueWedThuFriSatSun
0
  
  
  
  
  
  
  
1
  
  
  
  
  
  
  
2
  
  
  
  
  
  
  
3
  
  
  
  
  
  
  
4
  
  
  
  
  
  
  
5
  
  
  
  
  
  
  
6
  Monday at 6:00
  Tuesday at 6:00
  Wednesday at 6:00
  Thursday at 6:00
  Friday at 6:00
  Saturday at 6:00
  Sunday at 6:00
7
  Monday at 7:00
  Tuesday at 7:00
  Wednesday at 7:00
  Thursday at 7:00
  Friday at 7:00
  Saturday at 7:00
  Sunday at 7:00
8
  Monday at 8:00
  Tuesday at 8:00
  Wednesday at 8:00
  Thursday at 8:00
  Friday at 8:00
  Saturday at 8:00
  Sunday at 8:00
9
  Monday at 9:00
  Tuesday at 9:00
  Wednesday at 9:00
  Thursday at 9:00
  Friday at 9:00
  Saturday at 9:00
  Sunday at 9:00
10
  Monday at 10:00
  Tuesday at 10:00
  Wednesday at 10:00
  Thursday at 10:00
  Friday at 10:00
  Saturday at 10:00
  Sunday at 10:00
11
  Monday at 11:00
  Tuesday at 11:00
  Wednesday at 11:00
  Thursday at 11:00
  Friday at 11:00
  Saturday at 11:00
  Sunday at 11:00
12
  Monday at 12:00
  Tuesday at 12:00
  Wednesday at 12:00
  Thursday at 12:00
  Friday at 12:00
  Saturday at 12:00
  Sunday at 12:00
13
  Monday at 13:00
  Tuesday at 13:00
  Wednesday at 13:00
  Thursday at 13:00
  Friday at 13:00
  Saturday at 13:00
  Sunday at 13:00
14
  
  
  
  
  
  
  
15
  
  
  
  
  
  
  
16
  
  
  
  
  
  
  
17
  
  
  
  
  
  
  
18
  
  
  
  
  
  
  
19
  
  
  
  
  
  
  
20
  
  
  
  
  
  
  
21
  
  
  
  
  
  
  
22
  
  
  
  
  
  
  
23
  
  
  
  
  
  
  
from 172 SARAt student's home

Good-fit Instructor Guarantee


If you are not satisfied after your first lesson, Apprentus will find you another instructor or will refund your first lesson.

Online reputation

  • Instructor since October 2022

Availability of a typical week

(GMT -05:00) Chicago
MonTueWedThuFriSatSun
0
  
  
  
  
  
  
  
1
  
  
  
  
  
  
  
2
  
  
  
  
  
  
  
3
  
  
  
  
  
  
  
4
  
  
  
  
  
  
  
5
  
  
  
  
  
  
  
6
  Monday at 6:00
  Tuesday at 6:00
  Wednesday at 6:00
  Thursday at 6:00
  Friday at 6:00
  Saturday at 6:00
  Sunday at 6:00
7
  Monday at 7:00
  Tuesday at 7:00
  Wednesday at 7:00
  Thursday at 7:00
  Friday at 7:00
  Saturday at 7:00
  Sunday at 7:00
8
  Monday at 8:00
  Tuesday at 8:00
  Wednesday at 8:00
  Thursday at 8:00
  Friday at 8:00
  Saturday at 8:00
  Sunday at 8:00
9
  Monday at 9:00
  Tuesday at 9:00
  Wednesday at 9:00
  Thursday at 9:00
  Friday at 9:00
  Saturday at 9:00
  Sunday at 9:00
10
  Monday at 10:00
  Tuesday at 10:00
  Wednesday at 10:00
  Thursday at 10:00
  Friday at 10:00
  Saturday at 10:00
  Sunday at 10:00
11
  Monday at 11:00
  Tuesday at 11:00
  Wednesday at 11:00
  Thursday at 11:00
  Friday at 11:00
  Saturday at 11:00
  Sunday at 11:00
12
  Monday at 12:00
  Tuesday at 12:00
  Wednesday at 12:00
  Thursday at 12:00
  Friday at 12:00
  Saturday at 12:00
  Sunday at 12:00
13
  Monday at 13:00
  Tuesday at 13:00
  Wednesday at 13:00
  Thursday at 13:00
  Friday at 13:00
  Saturday at 13:00
  Sunday at 13:00
14
  
  
  
  
  
  
  
15
  
  
  
  
  
  
  
16
  
  
  
  
  
  
  
17
  
  
  
  
  
  
  
18
  
  
  
  
  
  
  
19
  
  
  
  
  
  
  
20
  
  
  
  
  
  
  
21
  
  
  
  
  
  
  
22
  
  
  
  
  
  
  
23
  
  
  
  
  
  
  
from 172 SARAt student's home

Good-fit Instructor Guarantee


If you are not satisfied after your first lesson, Apprentus will find you another instructor or will refund your first lesson.

Share


Afraa
Mathematics, computer, English, science. I teach primary school
Education has become a necessity, especially teaching basic subjects such as mathematics, science, and English, subjects that are not difficult to learn or understand. With a little understanding and focus, you will find yourself becoming well acquainted with them, so you must learn and understand them in order to succeed in your professional and academic life.

Raef
Private lessons in Math - Physics - Chemistry and SVT
Experienced professor graduated from the Faculty. of Sciences and the Fac. of Medicine of France, gives private lessons in Mathematics - Analysis - Matrices - Statistics - Algebra - Physics - Chemistry - Biology of French, Quebec CEGEP or International programs (in English) to students of secondary classes, Terminales, Brevet Concours and classes university preparatory courses for the 2022/2023 academic year. So that I can help students who take CNED and those who prepare for the SAT exams. The lessons will take place either at home or online using a specific, very modernized method, a shared interactive board equipped with writing tools where I can, with the student, write and correct homework by exposing them directly, in addition to Zoom or Skype to communicate (very practical method like at home). Results of my Terminale students since 2015: mentions Very good, Good and Excellent. Contact me for more details.

Sanne
Tutoring in chemistry for middle and high school students
*ENGLISH BELOW* Hello! My name is Sanne (23) and as a master student in Molecular Life Sciences I have a great passion for biochemistry. I have several years of experience and have helped more than 20 students with various science subjects. I offer tutoring for the subject of chemistry. Whether you need help with a specific chapter, or want to follow a broader exam training. During the tutoring we will mainly work together on assignments and I will support you in the thinking process. In addition to the lessons you will work independently on homework assignments. You will need a calculator and a Binas yourself. Tutoring in pairs or small groups (for example with classmates) is possible at a lower rate per person – please contact us for more information! *ENGLISH* My name is Sanne (23), and I'm a Master's student in Molecular Life Sciences with a strong passion for biochemistry. I have several years of tutoring experience and have helped over 20 students with various science subjects. I currently offer tutoring sessions in chemistry – whether you need help with a specific chapter or are looking for broader exam preparation. During our sessions, we'll work through exercises together, and I'll guide you through the thought process step by step. Between sessions, you'll work independently on homework assignments. You'll need your own calculator and a Binas (reference book). Tutoring in pairs or small groups (eg with a classmate) is possible at a reduced rate per person – feel free to get in touch for more details!

Bibek
CCVX + James Boswell Entrance Exams Preparation (Physics)
Hi! Welcome! I am a Ph.D. researcher in Physics at the University of Cologne, Germany. Recently, I graduated from the University of Groningen in the Netherlands with a Master's degree in Nanoscience (w/ cum Laude). I offer private tutoring (for high school and/or university-level students) so you can understand the fundamental concepts and excel in your studies. I have teaching experience of 5+ years in Physics and Mathematics to the high school and university-level students. This class aims to prepare you for the CCVX and James Boswell entrance examination in Physics so that you can enter the university. This course will be tailored to your specific needs, and we could mainly focus on the topics you are struggling with. Furthermore, please feel free to contact me and suggest any other topics you would like me to cover and teach. Topics of the course: 1. Mechanics 2. Oscillations and waves 3. Electrical circuits 4. Electric fields 5. Magnetic fields 6. Electromagnetic induction 7. Ray Optics 8. Pressure 9. Fluids and gases 10. Heat and thermodynamics 11. Sensors and automatic systems 12. Radiation and matter 13. Radioactivity and medical imaging 14. Nuclear energy 15. Light waves 16. Model of the atom 17. Basics of quantum mechanics and many more... *Note that the sessions will be held online (via Discord/Zoom/Microsoft Teams).

Mohamed
Private lessons in organic chemistry/advanced chemistry/analytical chemistry and spectroscopic technique
I give lessons in organic chemistry and general chemistry for all school levels at home and online CVs, courses and exercises are available, I can be reached immediately, do not hesitate to contact me if you want to improve your level in science (math, physics, general chemistry and organic chemistry in particular) I use several strategies and pedagogies (differentials, projects, group games, etc.) according to the needs of my students. I also use the links between science and our daily lives to attract and adore learning in my little angels. .

Ayoub
Private lessons for students of the French mission
I am committed to teaching my students while adopting an active teaching method. I put all my experience acquired as a private tutor at the service of their success. My seriousness, my listening and my kindness allow me to overcome difficulties and excel in: - Math, - Chemical Physics, My courses are aimed at students in the French system from 6th to 12th grade (Speciality: Mathematics, PC)

Benson
International Baccalaureate (IB) Diploma Programme: Chemistry / Biology / Physics / Mathematics
Work with me in your IB journey. I have over 6 years of teaching experience with international students from Europe, Asia and America. I give home works and assignments on a regular basis. Book a session with me in IB to get started. I interact with my students during lessons. After each lesson, i give students home works and assignment. The International Baccalaureate (IB) offers several programs in Europe, including the IB Diploma Programme, the European Baccalaureate, and the IB's Primary Years Programme, Middle Years Programme, and Career-related Programme:

Arrey Brenda
Chemistry, mathematics, English, GCESE exams prep, AP exam prep
Chemistry is the mother of science and we experience it's effect in every day human life. Learning chemistry could be challenging at times but with a determined mind you can . I've designed this course to give the in and outs of chemistry In this course we'll be looking at chemical bonding, atomic theory, kinetics, thermodynamics and many more to boost our knowledge of chemistry.

Andy
Tutor for Maths, Chemistry, Biology, and any test preparations.
I am a Chemistry student with 5 years of tutoring experience. I myself graduated from the IBDP with Chemistry, Biology and Math HLs and 777 at higher levels, thus, I am experienced with preparing students for examinations and tests as I myself have gone through that and am now at a higher level of my education in Chemistry.

Alexander Alvarenga
Industrial Engineering (Math/Physics and more.)
Industrial engineering at the university level is the branch of engineering that focuses on the design, improvement, implementation, and operation of production systems for goods and services. Its main objective is to optimize efficiency, increase productivity, and reduce costs in various organizations. Industrial engineers apply knowledge in areas such as operations management, methods and quality engineering, project management, and business administration. My tutoring sessions cover basic sciences (mathematics and physics), thermodynamics, and general subjects related to industrial engineering.

Kenneth
🇸🇬 [Grade 1 to 6] Singapore Math & Science Tutor 🇸🇬🇸🇬
Hi there! 👋 I’m a patient and passionate tutor from Singapore 🇸🇬 with several years of experience helping Primary school students (ages 6 to 12) build a strong foundation in Math and Science — the Singaporean way! I specialise in teaching Primary 1 to Primary 6, using proven methods from the Singapore MOE curriculum: ✅ clear explanations ✅ step-by-step problem-solving ✅ Real-life applications to make learning meaningful Whether your child needs extra support or wants to get ahead, I personalise every lesson to match their learning pace and style. My lessons are interactive, engaging, and focused on building confidence, not just completing worksheets. 🔹 Taught by a native Singaporean tutor 🔹 Lessons in English (with Chinese support if needed) 🔹 Concept mastery, test prep & homework help 🔹 Online sessions (with in-person options in Bangkok or Singapore) Let’s help your child feel more confident and capable — one fun and focused lesson at a time!

Sebastián
Chemistry Classes: Chemistry classes and tutoring are offered to high school and university students.
Do you want to learn chemistry? Do you find it difficult and think the subject is impossible? In the following Chemistry classes, you'll learn from the basics and progress until you fully understand the subject. I'll teach you using techniques and strategies that make the subject easy, simple, and fun for you, so you'll enjoy the time we spend learning. Like you, I'm young and I understand the difficulties involved in studying a subject like Chemistry. However, I've found methods and ways for you to learn from the most basic to the most advanced, and believe me, you'll learn a lot.

Arianit
Electrical Engineering I and II (Electrical Physics, Basics and Introduction, Electronics)
Electrical engineering forms the backbone of today's technology. From the distribution of electricity worldwide to the implementation of microcircuits, electrical engineering describes and provides the fundamentals of all principles pertaining to electronics, telecommunications, power systems, renewable energy, machines and mechatronics, etc. Having graduated as an Electrical Engineer I am offering Electrical Engineering I and II tutorials for beginner students at the University of Applied Sciences Upper Austria. I have experience in elaborating and describing the following thematics which are often problematic for students who seek a degree in Electronics Engineering, Computer Engineering, Telecommunication Engineering, and Electrical Engineering: •Electrical Engineering Basics •Conductor, Isolator, and Semiconductor Physics •AC Passive components: Inductors, Capacitors and Resistors •DC Circuit Analysis (Thevenin, Kirchhoff and Helmholtz approaches) •Three-phase systems •Diodes and the PN Junction •Transistor Physics: BJT/IGBT/MOSFET •Operational Amplifiers •Electronic Circuitry (Buffers, Signal Amplifiers, etc) •Transformer and Electromagnetics Basics

Maria
Mathematics and Physics Teacher : High School, A-level
Mathematics and Physics tutoring for all levels including A-level and High school in English. Classes can be done online or at home. I am a fully qualified Physics teacher (BSc) with experience in tutoring students up to undergraduate level.

Mouad
Mathematics Teacher - Mastery and Excellence - for Middle School - High School levels.
⭐⭐⭐⭐⭐ 👨‍🎓 With 4 years of experience in distance education, I am a mathematics teacher specializing in support lessons and private lessons. I also teach physics-chemistry and scientific subjects in general. I hold a Master's degree in Operational Research (Applied Mathematics) and I have been teaching private lessons for more than three years, mainly mathematics for middle and high school levels. ✏ I have taught students from various schools, whether public, private, following the French program (mission), Belgian, Swiss, Spanish (students from French-speaking or English-speaking Spanish schools) or American. In summary, all French or English programs. ✏ I support students from A to Z in all stages of their learning, using a simple, innovative and effective methodology: explanation of lessons, summary of lessons, application and deepening exercises, etc. ✏ I also prepare students for exams and competitions. ✏ I also support students with their homework (homework help). ✏ All my students have made extraordinary progress and achieved their goals, with grades of 16, 17, 18 or 19 out of 20. The sessions generally take place as follows: 1️⃣ The first sessions are mainly aimed at assessing the level of the student in order to identify the shortcomings observed. 2️⃣ Then we make a plan to fill those gaps: number of hours of work needed, parts of the lessons to focus on, lots of training and development exercises, etc. 3️⃣ We make sure to stay in regular contact with the student's class teacher to monitor their progress and align our work with what is being taught in class. 4️⃣ Then I provide exams similar to what may be offered in class. 5️⃣ Upon request, I write a monthly report to keep parents informed of their child's level throughout the course. I also adapt my methodology according to the needs of each student, which means that everyone has a personalized working method adapted to their needs! I also offer crash courses for those preparing for the start of the school year, so that they start the year well prepared 💪 and with a head start on the program.🧠 💭 If you have any questions, don't hesitate to contact me ;)