(type 3) Calculate mg per volume from mEq per volume

5. mEq and mOsmol 5.1) mEq 5.1.1) mEq - General

5.1.1.1) mEq from weight/volume Normal 1


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If lithium carbonate solution is expressed as 0.1351 mEq/mL, then how many milligram of lithium carbonate will be present in each 1 mL of the solution? Round to the nearest tenth. The molecular weight of lithium carbonate is 74 g/mol.


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lb equals 5 mg/1mL kg

    The molecular weight of lithium carbonate = 74.
    Valence or charge = 2.
    Therefore, we can write: 74 mg = 2 mEq.
    Since the question needs mg/1 mL as the final unit, we keep 74 mg in the starting numerator. So, 2 mEq will be the denominator.
    Also, the solution contains 0.1351 mEq per mL; therefore, the mEq is used as the numerator for the second fraction, in order to cancel out. The dimensional analysis will be like this:

    `(74 \quad mg)/(2 \quad mEq) × (0.1351 \quad mEq)/(1 \quad mL) × (1 \quad mL)/(1 \quad mL) = 5\quad (mg)/(1 \quad mL)` Ans.