Given :
Volume , V = 500 mL .
Molarity , M = 0.5 M .
Molecular mass of NaCl is
.
To Find :
How many grams of NaCl is required .
Solution :
Let , NaCl required is x gram .
Molarity is given by :

Hence , this is the required solution.
Answer:
Atomic radius of sodium = 227 pm
Atomic radius of potassium = 280 pm
Explanation:
Atomic radii trend along group:
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
Consider the example of sodium and potassium.
Sodium is present above the potassium with in same group i.e, group one.
The atomic number of sodium is 11 and potassium 19.
So potassium will have larger atomic radius as compared to sodium.
Atomic radius of sodium = 227 pm
Atomic radius of potassium = 280 pm
To convert boiling water to steam, that would involve heat of vaporization. The heat of vaporization for water at atmospheric conditions is: ΔHvap = <span>2260 J/g.
Molar mass of water = 18 g/mol
Q = m</span>ΔHvap = (1.50 mol water)(18 g/mol)(<span>2260 J/g) = 61,020 J
Time = Q/Rate = (61,020 J)(1 s/20 J) = 3051 seconds
In order to express the answer in three significant units, let's convert that to minutes.
Time = 3051 s * 1min/30 s = <em>102 min</em></span>
My guess is b for the question
<span>1mole of Cl atoms contain the Avogadro's number 6x10 exp 23(10 to the power of 23)
there for xmoles of Cl atoms is contained in 1.72x1022atoms
xmoles =1.72x1022 divided by 6x10exp 23
2.93 exp -23moles(2.93 x10 to the power of -23)
Hope It helped Let me know if did!!!!
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