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3 years ago

Which set of elements represents a period within the Periodic Table?

1 answer:

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Which set of elements represents a period within the Periodic Table?

H, He, Ar , Xe , Rn ,

N, P, As, Sb , Bi

K, V, Fe, Ga , Kr

La, Pa, Sm, Tb, Yb Which set of elements represents a period within the Periodic Table?

H, He, Ar , Xe , Rn ,

N, P, As, Sb , Bi

K, V, Fe, Ga , Kr

La, Pa, Sm, Tb, Yb

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An example of a physical property of an element is the element's ability to

FromTheMoon [43]

Answer:

dissolve

Explanation:

When it dissolves , no chemicals are formed and it is considered as a physical property.

4 0

3 years ago

Read 2 more answers

The enthalpy of solution (∆H) of KOH is -57.6 kJ/mol. If 3.66 g KOH is dissolved in enough water to make a 150.0 mL solution, wh

Wewaii [24]

When 3.66 g of KOH (∆Hsol = -57.6 kJ/mol) is dissolved in 150.0 mL of solution, it causes a temperature change of 5.87 °C.

The enthalpy of solution of KOH is -57.6 kJ/mol. We can calculate the heat released by the solution (Qr) of 3.66 g of KOH considering that the molar mass of KOH is 56.11 g/mol.

$3.66g \times \frac{1mol}{56.11g} \times \frac{(-57.6kJ)}{mol} = -3.76 kJ$

According to the law of conservation of energy, the sum of the heat released by the solution of KOH (Qr) and the heat absorbed by the solution (Qa) is zero.

$Qr+Qa = 0\\\\Qa = -Qr = 3.76 kJ$

150.0 mL of solution with a density of 1.02 g/mL were prepared. The mass (m) of the solution is:

$150.0 mL \times \frac{1.02g}{mL} = 153 g$

Given the specific heat capacity of the solution (c) is 4.184 J/g･°C, we can calculate the change in the temperature (ΔT) of the solution using the following expression.

$Qa = c \times m \times \Delta T\\\\\Delta T = \frac{Qa}{c \times m} = \frac{3.76 \times 10^{3}J }{\frac{4.184J}{g.\° C } \times 153g} = 5.87 \° C$

When 3.66 g of KOH (∆Hsol = -57.6 kJ/mol) is dissolved in 150.0 mL of solution, it causes a temperature change of 5.87 °C.

Learn more: brainly.com/question/4400908

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3 years ago

PLZ HELP ILL GIVE BRAINLIEST PLS 20 POINTS!!!

Nataly [62]

There is enough wind power in the U.S. to drive the entire country, but aesthetic considerations cause some people to oppose its use.

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3 years ago

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Find the potentials of the following electrochemical cell:

melomori [17]

Answer: 0.18 V

Explanation:-

$Cd/Cd^{2+}(0.10M)//Ni^{2+}(0.50M)?Ni$

Here Cd undergoes oxidation by loss of electrons, thus act as anode. nickel undergoes reduction by gain of electrons and thus act as cathode.

$E^0_(Cd^{2+}/Cd)$ =-0.40V[/tex]

$E^0_(Ni^{2+}/Ni)$ =-0.24V[/tex]

$Cd+Ni^{2+}\rightarrow Cd^{2+}+Ni$

Here Cd undergoes oxidation by loss of electrons, thus act as anode. nickel undergoes reduction by gain of electrons and thus act as cathode.

$E^0=E^0_{cathode}- E^0_{anode}$

Where both $E^0$ are standard reduction potentials.

$E^0=E^0_{[Ni^{2+}/Ni]}- E^0_{[Cd^{2+}/Cd]}$

$E^0=-0.24-(-0.40)=0.16V$

Using Nernst equation :

$E_{cell}=E^o_{cell}-\frac{0.0592}{n}\log \frac{[Cd^{2+}]}{[Ni^{2+]}$

where,

n = number of electrons in oxidation-reduction reaction = 2

$E^o_{cell}$ = standard electrode potential = 0.16 V

$E_{cell}=0.16-\frac{0.0592}{2}\log \frac{[0.10]}{[0.5]}$

$E_{cell}=0.18V$

Thus the potential of the following electrochemical cell is 0.18 V.

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3 years ago

Sodium is much more apt to exist as a cation than chlorine because:

8090 [49]

Answer:

(D) chlorine has a greater ionization energy than sodium

Explanation:

Sodium is the element of the group 1 and period 3 which means that the valence electronic configuration is $[Ne]3s^1$ .

Chlorine is the element of the group 17 and period 3 which means that the valence electronic configuration is $[Ne]3s^23p^5$ .

Ionization energy is the minimum amount of energy which is required to knock out the loosely bound valence electron from the isolated gaseous atom.

<u>Thus, removal of one electron in sodium is easy as it will gain noble gas configuration and become stable. But this case does not exist in chlorine and hence, chlorine has a greater ionization energy than sodium.</u>

So,

Sodium is much more apt to exist as a cation than chlorine because chlorine has a greater ionization energy than sodium.

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3 years ago