Unit 1: Water Analysis Overview
Engineering Chemistry Unit 1 focuses on water, its sources, impurities, hardness, alkalinity and industrial applications. Water is used in boilers, cooling systems, steam generation, chemical industries and power plants.
In RGPV exams, questions from this unit are commonly asked from hardness of water, temporary and permanent hardness, EDTA method, alkalinity determination and numerical problems.
Unit 1 Syllabus
- Introduction to Water
- Sources of Water
- Impurities in Water
- Hardness of Water
- Temporary and Permanent Hardness
- Units of Hardness
- Determination of Hardness by EDTA Method
- Alkalinity of Water
- Determination of Alkalinity
- Industrial Applications of Water
Most Important Topics for Exam
EDTA Method
Most important long-answer and numerical topic.
Hardness Numericals
Frequently repeated calculation-based question.
Temporary vs Permanent Hardness
Common 7-mark difference question.
Alkalinity Numericals
Very important titration-based numerical topic.
Short Notes for Quick Revision
1. Water
Water is an important natural resource used for domestic, agricultural and industrial purposes. In industries, it is mainly used for boilers, steam generation, cooling systems and chemical manufacturing.
2. Sources of Water
The main sources of water are rain water, surface water and underground water. Rain water is considered the purest natural source, while surface and underground water contain impurities.
3. Impurities in Water
Water may contain suspended impurities, dissolved salts, biological impurities and dissolved gases. These impurities affect the quality of water and may create industrial problems.
4. Hardness of Water
Hardness is the property due to which water does not form lather easily with soap. It is mainly caused by calcium and magnesium salts.
5. Temporary Hardness
Temporary hardness is caused by bicarbonates of calcium and magnesium. It can be removed by boiling.
6. Permanent Hardness
Permanent hardness is caused by chlorides and sulphates of calcium and magnesium. It cannot be removed by simple boiling.
7. EDTA Method
EDTA method is used to determine hardness of water. EDTA forms stable complexes with calcium and magnesium ions. Eriochrome Black-T is used as an indicator and the colour changes from wine red to blue.
8. Alkalinity of Water
Alkalinity is the capacity of water to neutralize acids. It is caused by hydroxides, carbonates and bicarbonates.
Formula Sheet
| Topic | Formula / Key Point |
|---|---|
| Hardness | (V × N × 50,000) / Sample Volume |
| Alkalinity | (V × N × 50,000) / Sample Volume |
| Temporary Hardness | Caused by bicarbonates; removed by boiling |
| Permanent Hardness | Caused by chlorides and sulphates; not removed by boiling |
| EDTA Indicator | Eriochrome Black-T |
| Alkalinity Indicators | Phenolphthalein and Methyl Orange |
| 1 ppm | 1 mg/L of CaCO3 |
Important Questions
- Define hardness of water.
- Differentiate temporary hardness and permanent hardness.
- Explain determination of hardness by EDTA method.
- Solve numerical problems based on EDTA method.
- Define alkalinity of water.
- Explain determination of alkalinity.
- Solve numerical problems based on alkalinity.
- Write industrial applications of water.
- Explain sources of water.
- Explain different impurities present in water.
PYQ Analysis Table
| Topic | Repeated Pattern | Importance |
|---|---|---|
| EDTA Method | Long answer + numerical | Very Important |
| Hardness of Water | Definition + numerical | Very Important |
| Temporary vs Permanent Hardness | Difference table | Very Important |
| Alkalinity | Definition + titration numerical | Very Important |
| Industrial Applications of Water | Short note | Important |
Sample Numericals
Hardness Numerical
Question: 50 mL water sample requires 10 mL EDTA solution of 0.01N. Calculate hardness.
Formula: Hardness = (V × N × 50,000) / Sample Volume
Solution: (10 × 0.01 × 50,000) / 50 = 100 ppm
Alkalinity Numerical
Question: 100 mL water sample requires 20 mL of 0.02N HCl. Calculate alkalinity.
Formula: Alkalinity = (V × N × 50,000) / Sample Volume
Solution: (20 × 0.02 × 50,000) / 100 = 200 ppm
Download Chemistry Unit 1 PDFs
Download complete notes, important questions and repeated PYQ analysis for Engineering Chemistry Unit 1.
Download Notes PDFHow to Prepare Unit 1
- First learn hardness, alkalinity and EDTA method definitions.
- Practice hardness and alkalinity formulas daily.
- Prepare temporary vs permanent hardness in table form.
- Revise EDTA indicator, colour change and procedure.
- Solve repeated PYQ numericals before exam.
Frequently Asked Questions
Is Chemistry Unit 1 important for RGPV exams?
Yes, Unit 1 is important because EDTA method, hardness numericals and alkalinity questions are repeatedly asked.
Which topic is most important in Unit 1?
EDTA Method, hardness numericals, temporary vs permanent hardness and alkalinity numericals are the most important topics.
Can I score good marks from this unit?
Yes, this unit is scoring if you practice formulas, definitions and repeated PYQ questions.
Is this website official?
No, this is an independent educational website created only for student support and exam preparation.