
好词典

源自拉丁语 'molaris',意为'磨石',与动词 'molere'(研磨)相关。14世纪进入英语,最初指磨碎的谷物,后引申为研磨牙齿。化学意义始于19世纪。
❶ 口腔后部用于咀嚼食物的牙齿,成年人类通常有12颗臼齿,包括智齿在内。
“The dentist said I need to have my molar extracted.”
(牙医说我需要拔掉这颗臼齿。)
“She bit into the apple with her back molars.”
(她用后臼齿咬了一口苹果。)
❶ 与摩尔量相关的化学术语,表示每升溶液中溶质的摩尔数。
“The molar concentration of the solution was 0.5 M.”
(该溶液的摩尔浓度为0.5M。)
“We need to calculate the molar mass of this compound.”
(我们需要计算这种化合物的摩尔质量。)
molar tooth — 特指臼齿,强调牙齿的咀嚼功能和解剖位置。
“The tiger's molar teeth are adapted for tearing meat.”
(老虎的臼齿适合撕咬肉类。)
molar concentration — 化学术语,表示单位体积溶液中所含溶质的物质的量。
“The molar concentration of NaCl in seawater is about 0.6 M.”
(海水中氯化钠的摩尔浓度约为0.6M。)