The element "X" is "O" (oxygen).
Given,
Chemical formula = Na₂CX₃
Formula mass = 106 amu
Molar mass of Na = 23 amu
Molar mass of C = 12 amu
To find,
Element X =?
We will equate the equation as follows,
2(23) + 12 + 3(y) = 106
46 + 12 + 3y =106
58 + 3y = 106
3y = 106 - 58
3y = 48
y = 48/3
y = 16
We know that Oxygen has molecular mass of 16. Therefore the element "X" is "O".
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