Answer:
Atomic size decreases from left to right in the Periodic Table.
Explanation:
s you move from left to right, the nucleus gains protons.
This increases the positive charge of the nucleus and its attractive force on the electrons.
At the same time, electrons are added to the atoms as you move from left to right across a period.
These electrons reside in the same energy shell and do not offer complete shielding.
The effect of the increasing proton number is greater than that of the increasing electron number.
As a result, the valence electrons are held closer to the nucleus, and the atomic radius decreases.
Answer : The correct option is, ![8.988\times 10^{-26}joules](https://tex.z-dn.net/?f=8.988%5Ctimes%2010%5E%7B-26%7Djoules)
Solution :
Formula used :
![E=\frac{h\times c}{\lambda}](https://tex.z-dn.net/?f=E%3D%5Cfrac%7Bh%5Ctimes%20c%7D%7B%5Clambda%7D)
where,
E = change in energy
h = Planck’s constant = ![6.626\times 10^{-34}J/s](https://tex.z-dn.net/?f=6.626%5Ctimes%2010%5E%7B-34%7DJ%2Fs)
c = speed of light = ![2.998\times 10^{8}m/s](https://tex.z-dn.net/?f=2.998%5Ctimes%2010%5E%7B8%7Dm%2Fs)
= wavelength = 2.21 m
Now put all the given values in the above formula, we get the energy of an atom.
![E=\frac{(6.626\times 10^{-34}J/s)\times (2.998\times 10^{8}m/s)}{2.21m}](https://tex.z-dn.net/?f=E%3D%5Cfrac%7B%286.626%5Ctimes%2010%5E%7B-34%7DJ%2Fs%29%5Ctimes%20%282.998%5Ctimes%2010%5E%7B8%7Dm%2Fs%29%7D%7B2.21m%7D)
![E=8.988\times 10^{-26}joules](https://tex.z-dn.net/?f=E%3D8.988%5Ctimes%2010%5E%7B-26%7Djoules)
Therefore, the energy of an atom is, ![8.988\times 10^{-26}joules](https://tex.z-dn.net/?f=8.988%5Ctimes%2010%5E%7B-26%7Djoules)
Convert particles to moles then moles to grams
Answer:
The mass of Potassium Sulphate required to prepare its ten percent(10%) solution in hundred gram(100g) of water is 11.11g. Explanation: Formula: mass of solute/mass of solution×100; A 10% mass solution in 100g of water means x/(100 + x) = 1/10 where x = mass required.
Answer:
Na
Explanation:
To find the limiting reactant we must first write the balanced chemical reaction. It must be correctly balanced so that we can find the proper mole ratios.
2 Na + H₂ → 2 NaH
After this we will convert our measurements to moles. For mass we do this by dividing by the molar mass.
6.75g ÷ 22.99 = 0.294mol Na
3.03g ÷ 2.02 = 1.50mol H₂
Now that we have the moles of each of the reactants, we can multiply them by their mole ratio with a reactant.
0.294mol Na ×
= 0.294mol NaH
1.50mol H₂ × 2/1 = 3.00mol NaH
Na is our limiting reagent because it makes the smaller amount of moles.