ʻO ka sodium carbonate (Na2CO3), ke kaumaha molekala 105.99.ʻOi aku ka maʻemaʻe o ke kemika ma mua o 99.2% (mass fraction), i kapa ʻia ʻo soda lehu, akā ʻo ka hoʻohālikelike ʻana i ka paʻakai, ʻaʻole ka alkali.ʻIke pū ʻia ʻo soda a i ʻole lehu alkali ma ke kālepa honua.He mea koʻikoʻi kemika inorganic ia, i hoʻohana nui ʻia i ka hana ʻana i ke aniani pālahalaha, nā huahana aniani a me nā glazes seramika.Hoʻohana nui ʻia ia i ka holoi ʻana, ka neutralization acid a me ka hana ʻai.