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Let T_(x%) denote the time required for x% completion of a first-order reaction. If T_(75%) = A * T_(50%), T_(87.5%) = B * T_(50%), and T_(99%) = C * T_(90%), find the value of A + B + C.
- 5
- 6
- 7
- 8
Correct answer: 7
Solution
A = T_(75%)/T_(50%) = 2ln2/ln2 = 2; B = T_(87.5%)/T_(50%) = 3ln2/ln2 = 3; C = T_(99%)/T_(90%) = ln100/ln10 = 2; so A+B+C = 7.
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