MCQ
Potassium has a $\ce{bcc}$ structure with nearest neighbour distance $4.525 \mathring A .$ Its molecular weight is $39.$ Its density in $kg/m^3$ is
- ✓$900$
- B$494$
- C$602$
- D$802$
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| List$-I$ | List$-II$ |
| $(a)$ $10\, km$ height over earth's surface | $(i)$ Thermosphere |
| $(b)$ $70\, km$ height over earth's surface | $(ii)$ Mesosphere |
| $(c)$ $180\, km$ height over earth's surface | $(iii)$ Stratosphere |
| $(d)$ $270\, km$ height over earth's surface | $(iv)$ Troposphere |