If a piece of bone such as femur of frog is kept in dilute HCl for about a week . It will

When a bone is kept in dilute acid for a few days, the salts get dissolved, leaving only soft and flexible organic matrix (decalcification). If kept in KOH, it remains unaffected, only the surrounding muscles and connective tissue get dissolved so that the bone now appears clean. If burned, the organic matter bums off producing smoke and the ash (mineral matter) is left behind