Answer:
c) (12×0.9889) + (13×0.01108)
Explanation:
Given data:
Percentage of C-12 = 98.89%
Percentage of C-13 = 1.108%
Atomic mass = ?
Solution:
98.89/100 = 0.9889
1.108/ 100 = 0.01108
Atomic mass = (12×0.9889) + (13×0.01108)
Atomic mass = (11.8668 + 0.144034)
Atomic mass = 12.01084
A beachside all objects have thermal energy but thermal energy is the sum of the energy of all the particles so the more particles the more energy.
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Answer:
1.07 g
Explanation:
Half-life of Pu-234 = 4.98 hours
Initially present = 45 g
mass remains after 27 hours = ?
Solution:
Formula
mass remains = 1/ 2ⁿ (original mass) ……… (1)
Where “n” is the number of half lives
To find "n" for 27 hours
n = time passed / half-life . . . . . . . .(2)
put values in equation 2
n = 27 hr / 4.98 hr
n = 5.4
Mass after 27 hr
Put values in equation 1
mass remains = 1/ 2ⁿ (original mass)
mass remains = 1/ 2^5.4 (45 g)
mass remains = 1/ 42.2 (45 g)
mass remains = 0.0237 x 45 g
mass remains = 1.07 g