BAC²
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For Lebanese Baccalaureate candidates — GS · LS · SE · LH

Your Lebanese Bac.
Under control.

Practise real Bac questions, get marked the way the exam marks you, ask Nour when you are stuck, and know exactly what to work on next.

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Examiner

Chemistry2021 · First SessionExercise 3

14/20

  • 4
    Correct method4
  • 3
    Explanation incomplete2
  • 2
    Missing justification0

Nour’s note

You identified the correct relationship, but the justification the barème asks for is not in your answer.

Pourquoi utilise-t-on cette relation ici ?

Nour

Because the system is isolated during this stage, no work is exchanged with the surroundings — so the total energy is conserved and the relation applies unchanged.

Grounded in your Bac

2022 · Second Session
Official solution
Physics · Mechanics
Textbook
2004—2024
of Lebanese Bac papers
5,297
past-exam questions
1,193
programme chapters
Official
barèmes and solutions, where the paper carries them

01Practice

Practise the questions that actually come up.

Real questions off real papers, filed by chapter against your own programme. Nothing in the library was written by a model.

ChemistryChemical equilibrium2021 · First Session

044 marks

A closed vessel contains an equilibrium mixture at 25 °C. Explain, with justification, how the position of equilibrium responds when the volume is halved at constant temperature.

02Examiner mode

See exactly where the marks went.

Your answer is read criterion by criterion against the paper’s barème — so you see what earned marks, what was partial, and what was missing.

Official barème · criterion by criterion

Chemistry

2021 · First session

Exercise 3

5 marks

Q3. Show that the reaction is complete.

Your answer

We determine the maximum advancement from the limiting reactant, H₃O⁺, which gives x_max = 2.0 × 10⁻³ mol.

B1 · Correct method+4

The final advancement measured in the experiment is x_f = 2.0 × 10⁻³ mol, so x_f = x_max.

B2 · Comparison stated, not explained+2 / 3

Expected by the barème

“…therefore the reaction is complete.”

B3 · Missing justification0 / 2

Nour’s note

You knew the chemistry. The two marks went on the sentence the barème asks for — say that x_f = x_max means the reaction is complete, and they are yours.

14/ 20

Pourquoi utilise-t-on cette relation ici ?

Nour

Because the system is isolated during this stage, no work is exchanged with the surroundings — so the total energy is conserved and the relation applies unchanged.

Grounded in your Bac

2022 · Second Session
Official solution
Physics · Mechanics
Textbook

03Nour

Meet Nour.
The tutor that knows your Bac.

Ask in Arabic, French or English. Nour answers from your programme and shows you the paper or the passage it came from — and says so plainly when your programme does not cover it.

Every answer carries what it was built from: the paper, the session, the marking scheme, the chapter. If it cannot be traced, Nour says so instead of inventing it.

04Your standing

Know where you stand.
Know what to fix.

Not a score out of nowhere. How well you do on what you have practised, how much of the programme you have covered, and how much marked work is behind both.

Your Bac

12.8/20

Readiness, from marked work

Mastery
72%
Practised
48%
Evidence
36 answers

Where marks go

  • Missing justification4 times
  • Incomplete conclusion3 times
  • Unit omitted2 times

Sample figures, shown to illustrate the interface.

05Next move

Less wondering. More knowing what to do next.

One instruction at a time, drawn from your own marks — not a feed of everything you could theoretically be doing.

Your next move

Chemistry

Chemical equilibrium

You have practised this chapter, but recent answers are still losing marks on justification.

Practise 3 questions

06Your Bac

Built around your Bac.
Not adapted to it.

Four tracks, three languages of instruction, one programme. Your subjects arrive in the language they are examined in, and the interface stays in yours.

Tracks

GS·LS·SE·LH

Languages of instruction

العربية

History · Arabic

علّل أسباب اندلاع الحرب العالمية الأولى، مستندًا إلى الوثائق المرفقة.

Français

Mathematics · French

Déterminer la limite de la fonction f en +∞, puis interpréter graphiquement.

English

Biology · English

Explain how the structure of the nephron supports selective reabsorption.

Chemistry2021 · First SessionExercise 3

014 marks

A closed vessel contains an equilibrium mixture at 25 °C. Explain, with justification, how the position of equilibrium responds when the volume is halved at constant temperature.

07Mock exams

When you’re ready,
sit the paper.

A real past paper or one assembled from real questions, on a clock, marked at the end. The timing is the paper’s own where we hold it, and ours where we do not — and the page tells you which.

It’s one loop, not seven tools.

  1. 01

    Practise

  2. 02

    Get marked

  3. 03

    See what it cost

  4. 04

    Know what to study

  5. 05

    Sit it again

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Bac II — Your Lebanese Bac. Under control.