Mendeleev's periodic table had anomalies because he arranged elements by: MCQ with Answer and Explanation

Explanation:
Atomic number = 2+8+7=17 (chlorine). Period = number of shells = 3. Valence electrons = 7 → Group 17 (10+7 for p-block). Group 18 has 8 valence electrons.

Explanation:
Ernest Rutherford, along with his students Geiger and Marsden, conducted the famous gold foil experiment in 1911. By observing that a few alpha particles bounced back, he concluded that the atom has a small, dense, positively charged center called the nucleus.

Explanation:
Detergents emulsify grease by forming micelles around oil droplets, removing them from fabric. Soap does same but less effective in hard water.