Answer: Between 1 and 2.
Explanation:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
............(1)
where,
a = amount of reactant left after n-half lives = 40
= Initial amount of the reactant = 100
n = number of half lives
Putting in the values we get:

taking log on both sides


Thus half-lives that have elapsed is between 1 and 2
Q= mcΔT
1623 = 33.69g x c x (110.8 - 29.4)
1623 = 2742.366 g•°C x c
c = 0.59j/g•°C
Answer:
The boiling point of water is a physical property and is equal to 0 C.
The Correct Answer is : C
1 mol = 6.023x10^23 number of molecules (Avogadro's number)
1 : 6.023x10^23
X : 4.91x10^22
(6.023x10^23)X = 4.91x10^22
X = 4.91x10^22/6.023x10^23
X = 0.082 Moles