Answer:
0.5 mol
Explanation:
Given data:
Number of atoms of He = 3.01 ×10²³
Number of moles = ?
Solution:
Avogadro number:
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.02 × 10²³ is called Avogadro number.
1 mole = 6.02 × 10²³ atoms
3.01 ×10²³ atoms × 1 mol / 6.02 × 10²³ atoms
0.5 mol
Answer:
Si₁₄ = 1s² 2s² 2p⁶ 3s² 3p²
Explanation:
Silicon is present in group 14 of periodic table.
It is blue-gray color metalloid.
Its atomic mass is 28 g/mol.
It is mostly used to make allow.
The most important alloy are Al-Si and Fe-Si. These are used to make different machine tools, transformer plates, engine etc.
Its atomic number is 14 and electronic configuration can be written as,
Electronic configuration:
Si₁₄ = 1s² 2s² 2p⁶ 3s² 3p²
The noble gas electronic configuration or abbreviated electronic configuration can also be written.
Si₁₄ = [Ne] 3s² 3p²
The atomic number of neon is 10. Its electronic configuration is,
Ne₁₀ = 1s² 2s² 2p⁶
That's why we write [Ne] for 1s² 2s² 2p⁶ in abbreviated electronic configuration of Si.
Answer:
The correct solution is "3.28 m".
Explanation:
According to the question,
Mol fraction of solvent,
= 0.0558
Molar mass of water,
= 18 g/mol
Mol of H₂O in 1000 g water,
= 55.55 mol
Now,
Let the mol of solute will be "x mol".
Total mol in solution will be "55.55 + x".
As we know,
⇒ The mol fraction of solvent = 

![x=0.0558[55.55+x]](https://tex.z-dn.net/?f=x%3D0.0558%5B55.55%2Bx%5D)

