Answer: a) The concentration after 8.8min is 0.17 M
b) Time taken for the concentration of cyclopropane to decrease from 0.25M to 0.15M is 687 seconds.
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) concentration after 8.8 min:



b) for concentration to decrease from 0.25M to 0.15M


Answer: 1.9 x 10²⁴ molecules Na
Explanation: To solve for the molecules of Na, we will use the Avogadro's number.
3.2 moles Na x 6.022 x10²³ molecules Na/ 1 mole Nà
= 1.9 x 10²⁴ molecules Na
Opposite pairs form ionic bonds, due to this the answer is D - Li and Br; They have unlike charges.
Answer : The correct option is, 
Explanation :
- Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. That means, the loss of electrons takes place.
Or we can say that, oxidation reaction occurs when a reactant losses electrons in the reaction.
- Reduction reaction : It is defined as the reaction in which a substance gains electrons. That means, the gain of electrons takes place.
Or we can say that, reduction reaction occurs when a reactant gains electrons in the reaction.
According to the electrochemical series,
most likely to be reduced because
Hence, the ion most likely to be reduced is
.