4.08g of a mixture of BaO and unknown carbonate $(MCO_3)$ was heated strongly.The residue of 3.64g was dissolved in 100ml of 1N HCl.The excess acid required 16ml of 2.5N NaOH solution for complete neutralization.Identify metal

Question

$(a)\;S\qquad(b)\;Ca\qquad(c)\;Fe\qquad(d)\;Na$