123456KeyworddeuteriumFrequency#5477Strokes6ReadingsdāoMnemonic气 (gas) gives the meaning and 刂 the sound.Stroke orderComposed of气gas刂knifeUsed in vocabulary氘dāodeuterium 2H; heavy hydrogen, isotope of hydrogen having 1 neutron in its nucleus, so atomic weight 2氘核dāohédeuteron