设NA代表阿伏加德罗常数的值,下列说法正确的是 A.0.1mol H2O和D2O组成的混合物中含有中子数是NA B.28g N60(分子结构如右图所示)中含有的N—N键数目为1.5NA C.25℃、1.01×105Pa时,16g氧气中所含的原子数为NA D.常温下浓度都为0.1mol/L,体积相等的NaF和CH3COONa溶液中,离子数目都为0.2NA
—Have you ever ______ the charity walk ? —Not yet.
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A. heard from B. listen to C. heard about D. hear of