The answer to this question would be: <span>cs
</span>
Electron affinity is determined by the amount of energy released/spent for the atom to add an electron for neutral atoms in gas state.
Lower periodic table means a bigger radius atom. In this case, the distance between the electron to the nucleus is further too, so the affinity is expected to become lower.
In this question, the K and Cs are located in the first column of the periodic table, but Cs located lower. So, the Cs that located lower in periodic table should have a lower affinity.
D. A broken piece of quartzite will break through, not around, quartz sand grains.
Quartzite and quartz sandstone have the <em>same chemical formula</em> (SiO_2)
Quartzite is a <em>metamorphic rock</em>. Heat and pressure have compressed the sand into a strong network of interlocking quartz grains.
Quartzite is so tough that it breaks through the sand grains rather than around them as in sandstone.
<span>Eight Planets<span>There are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
But don't we wish for Pluto! :(</span></span>
False
Explanation:
because every problem of a mankind has a solution
