**Answer:**

Si

**Explanation:**

Dispersion force or London force is the force of attraction between two atoms or molecules in a substance in solid , liquid and gas . In gas , this force is minimum and in solid this force is maximum . In solid this force is maximum in metals in which this force forms metallic bond .

Among the given substances , Si , Sn , MgO , C₂₀H₄₂ are solid , so dispersion force will be high in them .

Among all as mentioned above , Si will have highest dispersion force . It is due to four covalent bond that bind two atoms of Si in solid silicon . Its three dimensional crystal structure consist of silicon atoms , all bound by four covalent bonds .

**Answer:**

ribosome i think or cant u google that

**Explanation:**

Total volume of the solution will be (10 ml + 10 ml) = 20 ml. As there are 1000 ml in 1 L. So, 20 ml will be equal to 0.02 L.

As molarity equals number of moles divided by volume in liter. Hence, calculate number of moles of as follows.

No. of moles =

=

= mol

Hence, moles of will also be equal to mol.

Now, calculate the no. of moles of as follows.

No. of moles =

=

= mol

As there are 2 ions in 1 mole of . Hence, in mol number of ions will be mol.

When both the solutions are mixed together then molarity of the solution will be calculated as follows.

Molarity of solution =

=

= 0.015 M

Thus, we can conclude that **the molar concentration of Na (aq) in the given solution is 0.015 M.**

It’s the first two answers isn’t it? Because xy=k is inverse