Hence, it is less preferrable to choose an isotope to enter your body, which will emit radioactivity for a long time, so we tend to choose isotopes, the radioactivity of which ceases quickly, so that the least possible amount of damage is caused to the cells
Hey there!
H₃PO₄
Find molar mass.
H: 3 x 1.008 = 3.024
P: 1 x 30.97 = 30.97
O: 4 x 16 = 64
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97.994 grams
The mass of 1 mole of H₃PO₄ is 97.994 grams.
We have 4.5 moles.
97.994 x 4.5 = 440
The mass of 4.5 moles of H₃PO₄ is 440 grams.
Hope this helps!