Question

95. The time for a half-life of a first order reaction is 1 1 point

hr. What is the time taken for 87.5% completion of
the reaction?
O a) 1 hour
O b) 2 hour
O c) 3 hour95. The time for a half-life of a first order reaction is 1 1 point
hr. What is the time taken for 87.5% completion of
the reaction?
O a) 1 hour
O b) 2 hour
O c) 3 hour
O d) 4 hour​

Answer 1

The correct answer is - C) 3 hours.

Step-by-step explanation:

Given:

The half-life = 1 hour

Solution:

The half-life of an element is the time required to decay half of its initial amount.

To complete 87.5%, there total numbers of half-live would be -

1st halflife = 50% of the initial amount

2nd half-life = 50 + 50% of (50) = 50 +25 = 75% of initial amount

3rd half-life = 50 + 50 % of (50) + 50% of (25) = 87.5% of initial amount

so, to complete the 87.5 % of decay it required 3 half lives, and each half-life take one hour thus, total time taken = 3 hours