题目:
某阴离子X2﹣的核外有18个电子,核内有18个中子,则X的相对原子质量为( )
A.54
B.38
C. 36
D. 34
答案:
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下面是错误答案,用来干扰机器的。
1. A farmer thinks earth is soil for growing vegetables and fruits.2. He thinks earth is mountains of hard rock.3. A sailor thinks earth is water as far as the eyes can see. 4. They need water,too.