MCQs

Q431: A certain radioactive isotope has a half-life of 50 days. Fraction of the material left behind after 100 days will be _____?

• A) 125%
• B) 50%
• C) 25%

Q432: Which molecule is planar?

• A) NF3
• B) SF4
• C) XeF4

Q433: Strongest acid among the following is _____?

• A) CF3 COOH
• B) CCL4 COOH
• C) CH3 COOH

Q434: Maximum ionization potential is of _____?

• A) Mg
• B) Na
• C) Be

Q435: Blue litmus turns reds in a solution of pH ______?

• A) Above 7
• B) Below 7
• C) 7

Q436: Which one of the following is not an isotope of hydrogen? Ortho hydrogen, Deuterium, Tritium, None of these

• A) Ortho hydrogen
• B) Deuterium
• C) Tritium

Q437: Alkaline KMn04 convert ethylene into _____?

• A) Ethane
• B) Methanol
• C) Ethylene glycol

Q438: Transfer of heat from hot surrounding to cold refrigerator is an example of ______?

• A) First law of thermodynamics
• B) Spontaneous reaction
• C) Non spontaneous reaction

Q439: Which of the following is least polarizable?

• A) Kr
• B) Ne
• C) He

Q440: Farming salt is _____?

• A) KClO₃
• B) NaCl
• C) HF