A.) half - life of a radioactive substance is defined as the time during which concentration of the substance becomes half the initial value.
<h2>Answer:</h2>
Option A is correct
Adding an enzyme to decrease the activation energy of the reaction
<h2>Explanation:</h2>
Enzymes are the biological catalyst. They are proteins in nature. They are naturally found in humans,animals,micro-organisms,plants etc. They catalyze the chemical reactions by lowering activation energy and without being consumed in it.
This statement would be best characterized by the law of conservation of momentum—choice C.
Answer:
Periodic but not oscillatory
Explanation:
The Orbital motion of the earth around the sun is not an oscillatory motion as it is not a two and Fro motion about a mean position. But it is a periodic motion.
