Answer:
= 3/4
Explanation:
Half life is the time taken by a radioactove element to decay by half of its original mass.
The half life of tritium is 12.3 years , therefore it would take 12.3 years for tritium to decay to a half its original mass.
Using the formula;
New mass = Initial mass × (1/2)^n ; where n is the number of half lives.
n = 5.2 years/12.3 years
= 52/123
Therefore;
New mass = 1 × (1/2)^(52/123)
= 0.74599
= 0.75
The fraction of a tritium sample after 5.20 years will be approximately 3/4
Answer:
3.61 * 10 ²⁴atoms.
Explanation:
Moles is denoted by given mass divided by the molecular mass ,
Hence ,
n = w / m
n = moles ,
w = given mass ,
m = molecular mass .
From the question ,
w = 582 g
m = 194 g/mol
The number of moles can be calculated from the above formula , and substituting the respective values ,
n = w / m = 582 g / 194 g/mol = 3 mol
In the molecular formula of caffeine ,
<u>In 1 mole of caffeine their are - 2 moles of Oxygen.
</u>
Therefore , in 3 moles of Caffeine there will be 6 moles of oxygen.
As well know ,
one mole of any substance contains 6.023*10²³ atoms,
Therefore , in 6 mol of oxygen = 6 * 6.023*10²³ atoms = 3.61 * 10 ²⁴atoms.
Answer:
c. 5days
Explanation:
there is no question but if it's a graph
the answer is 5days
