英语语法分析

And how is it known that Mars had hafnium-187?

那么是如何知道火星有铪- 187的呢？

Chemical form of hafnium is perchlorate or nitrate.

铪的化学形态为过氯酸盐或硝酸盐。

Mainly because the quantity of hafnium, utilized in one chip, is negligibly small.

这主要是因为数量的铪，利用一个芯片，是微乎其微的小。