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3 years ago

Who made the idea that as you go down the periodic table the atomic radius increases and the first ionization energy decreases?

Chemistry

2 answers:

bekas [8.4K]3 years ago

7 0

<u>Answer:</u>

The idea that as we go down the periodic table the atomic radius increases and first ionization energy decreases was given by Henry Moosely after he made some changes in the periodic table, the theory proposed by Mendeleev.

<u>Explanation:</u>

Both these trends were well explained and supported by genuine reasons.
As we go down a group in periodic table, a new shell is added at each level, which increases the size and hence the radius of the atom and the size of atom increases which means the outermost shell is increasingly moving farther from the atom.
Due to this fact, electrons experience less attractive force from the nucleus and electrons are easily removed, so the first ionization energy decreases.

Semenov [28]3 years ago

7 0

<h2>Henry Moseley made the idea that as you go down the periodic table the atomic radius increases and the first ionization energy decreases</h2>

Explanation:

Mosely revised the periodic table trend devised by Mendelev by changing the criterion of atomic mass to atomic number.

The atomic number defines the atomic radius as well as ionization energy trends in the periodic table. The atomic number or the number of positively charged protons determines the atomic radius. With increase in positive charge, the atomic radius decreases due to electron proximity towards the nucleus.

In a periodic table:

Across a period – nuclear charge increases, a greater attraction between the valence shell electron and nucleus

Down a group – nuclear charge increases, shielding increases due to more electron shells, a lesser attraction between the valence shell electron and nucleus. Based on this,

Across a period – atomic radius decreases and first ionization energy increases

Down a group – atomic radius increases and first ionization energy decreases

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Why does the periodic table have the shape it has

Orlov [11]

Answer: The arrangement of electrons in atoms is responsible for the shape of the periodic table.

Explanation: Electron configurations can be predicted by the position of an atom on the periodic table.

O_O O_O O_O

Add me as a freind!!! <3

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3 years ago

217 mL of neon gas at 551 celsius is brought to standard temperature (0 celsius) while the pressure is held constant. What is th

pantera1 [17]

Answer: The new volume is 72 ml

Explanation:

To calculate the final volume of the system, we use the equation given by Charles' Law. This law states that volume of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

$\frac{V_1}{T_1}=\frac{V_2}{T_2}$

where,

$V_1\text{ and }T_1$ are the initial volume and temperature of the gas.

$V_2\text{ and }T_2$ are the final volume and temperature of the gas.

We are given:

$V_1=217ml\\T_1=551^oC=(551+273)K=824K\\V_2=?\\T_2=0^0C=(0+273)K=273K$

Putting values in above equation, we get:

$\frac{217ml}{824K}=\frac{V_2}{273K}\\\\V_2=72ml$

Thus the new volume is 72 ml

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2 years ago

Devante buys a helium birthday balloon for his mom at the grocery store, where the temperature is a comfortable 72oF. He takes t

frozen [14]

The balloon would be smaller and not float as well because of the low temperature. The particles in the balloon when in the car will slow down and get closer together because of the low temperature. That caused it to become more dense and smaller in size then before. When in the store, the particulars in the balloon we’re moving faster and more spread apart

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3 years ago

Find the percentage composition for iron in the following compound Fe2(CO3)3

schepotkina [342]

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3 years ago

In Part III, the phenolphthalein indicator is used to monitor the equilibrium shifts of the ammonia/ammonium ion system. The phe

AnnZ [28]

The pink color in the solution fades. Some of the colored indicator ion converts to the colorless indicator molecule.

<h3>Explanation</h3>

What's the initial color of the solution?

$\text{NH}_4\text{Cl}$ is a salt soluble in water. $\text{NH}_4\text{Cl}$ dissociates into ions completely when dissolved.

$\text{NH}_4\text{Cl} \; (aq)\to {\text{NH}_4}^{+} \; (aq) +{\text{Cl}}^{-} \; (aq)$ .

The first test tube used to contain $\text{NH}_4\text{OH}$ . $\text{NH}_4\text{OH}$ is a weak base that dissociates partially in water.

$\text{NH}_4\text{OH} \; (aq) \rightleftharpoons {\text{NH}_4}^{+} \;(aq)+ {\text{OH}}^{-} \; (aq)$ .

There's also an equilibrium between $\text{OH}^{-}$ and ${\text{H}_3\text{O}}^{+}$ ions.

${\text{OH}}^{-}\;(aq) + {\text{H}_3\text{O}}^{+} \;(aq) \to 2\; \text{H}_2\text{O} \;(l)$ .

$\text{OH}^{-}$ ions from $\text{NH}_4\text{OH}$ will shift the equilibrium between $\text{OH}^{-}$ and ${\text{H}_3\text{O}}^{+}$ to the right and reduce the amount of ${\text{H}_3\text{O}}^{+}$ in the solution.

The indicator equilibrium will shift to the right to produce more ${\text{H}_3\text{O}}^{+}$ ions along with the colored indicator ions. The solution will show a pink color.

What's the color of the solution after adding NH₄Cl?

Adding $\text{NH}_4\text{Cl}$ will add to the concentration of ${\text{NH}_4}^{+}$ ions in the solution. Some of the ${\text{NH}_4}^{+}$ ions will combine with $\text{OH}^{-}$ ions to produce $\text{NH}_4\text{OH}$ .

The equilibrium between $\text{OH}^{-}$ and ${\text{H}_3\text{O}}^{+}$ ions will shift to the left to produce more of both ions.

${\text{OH}}^{-}\;(aq) + {\text{H}_3\text{O}}^{+} \;(aq) \to 2\; \text{H}_2\text{O} \;(l)$

The indicator equilibrium will shift to the left as the concentration of ${\text{H}_3\text{O}}^{+}$ increases. There will be less colored ions and more colorless molecules in the test tube. The pink color will fade.

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3 years ago