Soaps / साबुन
The source defines soaps as sodium and potassium salts of higher fatty acids.
Soaps higher fatty acids के sodium अथवा potassium salts होते हैं।
Examples mentioned include sodium palmitate and sodium stearate.
Glass / काँच
The source describes glass as an amorphous solid or super-cooled liquid containing mainly silica, SiO₂.
Source Glass को amorphous solid अथवा super-cooled liquid बताता है जिसमें mainly Silica (SiO₂) होता है।
Colours of Glass / काँच के रंग
Different substances are added to obtain glass of different colours.
- Red → Copper oxide (CuO)
- Green → Chromium oxide (Cr₂O₃)
- Ruby Red → Gold chloride (AuCl₃)
- Blue → Cobalt oxide (CoO)
- Brown → Iron oxide (Fe₂O₃)
Competitive exams में coloured glass के लिए added compound से direct matching questions पूछे जा सकते हैं।
Heavy Water / भारी जल
Heavy water is deuterium oxide, D₂O. The source gives its molecular mass as 20 and states that it is used as a moderator in nuclear reactors.
Heavy Water का chemical formula D₂O है। इसमें ordinary hydrogen के स्थान पर heavy hydrogen अर्थात Deuterium present होता है। Source इसे nuclear reactor में moderator के रूप में बताता है।
Important Fact / महत्वपूर्ण तथ्य
Heavy Water → D₂O → Moderator in Nuclear Reactor
Hard Water / कठोर जल
The source distinguishes temporary hardness and permanent hardness according to the dissolved salts present in water.
Temporary Hard Water / अस्थायी कठोर जल
Water containing soluble bicarbonates of calcium and magnesium is called temporary hard water.
Calcium और Magnesium के soluble bicarbonates की presence से Temporary Hardness होती है।
Permanent Hard Water / स्थायी कठोर जल
Water containing soluble sulphates and chlorides of calcium and magnesium is described as permanently hard.
Calcium तथा Magnesium के soluble sulphates और chlorides की presence से Permanent Hardness होती है।
Removal of Temporary Hardness / अस्थायी कठोरता हटाना
- Boiling / उबालना
- Adding calcium hydroxide, Ca(OH)₂ / Calcium hydroxide add करना
- Clark's Process / Clark Process
Removal of Permanent Hardness / स्थायी कठोरता हटाना
- Sodium carbonate, Na₂CO₃
- Calgon, identified by the source as sodium hexametaphosphate
Hardening of Oil or Hydrogenation / तेल का कठोरीकरण या हाइड्रोजनीकरण
The source states that an unsaturated oil heated with hydrogen in the presence of nickel catalyst gets converted into a solid saturated fat described as ghee.
Unsaturated Oil को Hydrogen के साथ Nickel catalyst की presence में heat करने पर solid saturated fat में convert किया जाता है। इस process को Hydrogenation या Hardening of Oil कहते हैं।
Exam Formula / परीक्षा तथ्य
Unsaturated Oil + Hydrogen —Ni→ Saturated Fat
Quick Revision / त्वरित पुनरावृत्ति
- Soap → Sodium/Potassium salts of higher fatty acids
- Glass → Mainly SiO₂
- Blue glass → Cobalt oxide
- Green glass → Chromium oxide
- Heavy water → D₂O
- Temporary hardness → Bicarbonates
- Permanent hardness → Sulphates and chlorides
- Hydrogenation catalyst → Nickel