8.1moles
Explanation:
Given parameters:
Mass of water to be decomposed = 29.2g
Unknown:
Number of moles of oxygen.
Solution:
To solve this problem, we first write the balanced reaction equation :
2H₂O → 2H₂ + O₂
Now convert the given mass of the water to number of moles;
Number of moles of water = 
Molar mass of water = 2(1) + 16 = 18g/mol
Number of moles of water =
= 16.2moles
From the balanced reaction equation:
2 moles of water produced 1 mole of oxygen gas;
16.2 mole of water will produce
= 8.1moles of oxygen gas
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Number of moles brainly.com/question/1841136
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Answer:
Use the activity formula,
T1/2 = 4.468 x 10^9 yr x 365 x 24 x 3600 = 1.409 x 10^17 sec
l = ln(2)/T1/2 = ln(2)/1.409 x 10^17 = 4.91932697 x 10^-18 s-1
DN/Dt = lN, 265 = 4.91932697 x 10^-18 x N
<u><em>N = 5.38 x 10^19 nuclei</em></u>