MCQ
Internal energy does not include:
- AVibrational energy
- BRotational energy
- CEnergy arising by gravitational pull
- DNuclear energy
Explanation:
Energy arising by gravitational pull is not included in internal energy. Its external energy.
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| Element | $IE_1$ | $IE_2$ | $IE_3$ | $IE_4$ |
| $W$ | $10.5$ | $15.5$ | $24.9$ | $79.8$ |
| $X$ | $8$ | $14.8$ | $78.9$ | $105.8$ |
Other two elements $Y$ and $Z$ have outer electronic configuration $ns^2$ $np^4$ and $ns^2$ $np^5$ respectively. According to given information which of the following compound $(s)$ is/are not possible
$(a)\, W_2Y_3\, (b)\, X_2Y_3\, (c)\, WZ_2\, (d)\, XZ_2$
| List $I$ (Mixture) | List $II$ (Separation Technique) |
| $A$ $CHCl _3+ C _6 H _5 NH _2$ | $I$ Steam distillation |
| $B$ $C _6 H _{14}+ C _5 H _{12}$ | $II$ Differential extraction |
| $C$ $C _6 H _5 NH _2+ H _2 O$ | $III$ Distillation |
| $D$ Organic compound in $H _2 O$ | $IV$ Fractional distillation |
$I_{2(g)} \rightleftharpoons 2I_{(g)} ; \Delta_f H^o = +150\,kJ$
The forward reaction is favoured at