Salt is soluble in water, sand is not. Add water, stir to dissolve salt, filter to separate sand. Then evaporate the filtrate to recover salt. Sublimation separates sublimable solids (NH₄Cl, naphthalene). Magnetic for magnetic materials. Fractional distillation for liquid mixtures. This is a standard separation technique.
Assertion (A): The smell of hot sizzling food reaches you several meters away, but to get the smell from cold food you have to go close. Reason (R): The kinetic energy of gas molecules is higher at higher temperatures.
A.Both A and R are true and R is the correct explanation of A.
B.Both A and R are true but R is NOT the correct explanation of A.
Explanation:
At higher temperatures, the rate of diffusion increases because the kinetic energy of the gas molecules (food aroma) increases. Thus, the smell of hot food diffuses faster and reaches further. Both statements are correct, and the increased kinetic energy perfectly explains the enhanced diffusion rate observed in the assertion.
Explanation:
Fermentation is an anaerobic biological process in which enzymes (zymase) convert glucose to ethanol and CO₂: C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂. Oxidation would require oxygen. Esterification forms esters, saponification makes soap. Fermentation is used in brewing, winemaking, and baking (where CO₂ makes bread rise). The temperature is kept around 30-35°C.
Explanation:
Calcium (Ca) has a valency of +2, and the phosphate ion (PO₄) has a valency of -3. To balance the charges, we need three calcium ions and two phosphate ions, giving the formula Ca₃(PO₄)₂. This is determined by criss-crossing the valencies of the constituent ions.
No comments yet. Be the first to start the discussion!