Toxin
The formula for limestone is CaCO3 and hydrocloric acid is HCL. Therefore they undergo a acid + metalcarbonate reaction. acid + metal carbonate -> salt +water + carbon di oxide. So when limestone reacts with HCl it prodcues salt (CaCl2) , water (H2O) and carbon di oxide (CO2(bubbles)). thus limestone reacts with HCl
The endocrine system creates hormones and the glands of the system release them into the body.