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2 years ago

In terms of atomic structure, explain why the atomic radius of K is larger than that of Na

Chemistry

1 answer:

oee [108]2 years ago

7 0

Answer:

Explanation:

Sodium and potassium are present in group 1A. Both are alkali metals.

The atomic number of sodium is 11 and potassium is 19. Sodium is present in period 3rd while potassium is present in period 4th.

Electronic configuration of sodium:

Na₁₁ = 1s² 2s² 2p⁶ 3s¹

K₁₉ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹

It can be seen in electronic configuration that in case of sodium the valance electron is present in third energy level while in case of K outer most electron is present in 4th energy level. So atomic structure of sodium has three energy level and K has four energy level that's why radius of potassium is greater than sodium because its the distance from center to outer most electronic shell.

Moreover 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.

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The diagram below shows the different phase transitions that occur in matter. Which arrow represents the transition in which dew

oksian1 [2.3K]

Answer:

The arrow labeled 4: from gas to liquid.

Explanation:

Dew is a manifestation of water condensation.

The air that surrounds us contains water vapor (humidity) from the evaporatoin of the water in the rivers, lakes, and the water with which you water the plants of your garden.

During the night, and specially in the early morning, before dawn, the temperature of the air descends, and part of the vapor in the air condensates in tiny droplets that accumulate over the surface of the plant's leaves, and other solid surfaces like the winshields and hoods of the cars.

Then, the phase transition that occurs is from gas (vapor) to liquid, which is called condensation and represented with the arrow labeled 4 on the diagram.

3 0

1 year ago

Read 2 more answers

Which liquid materials have strong odor and weak odor?

densk [106]

Odor refers to the fragrance caused by one or more volatilized chemical compounds. It can be strong or weak. 
Strong odor have: Sodium Hypochlorite, Muriatic Acid, Sulphuric Acid, Ammunlom Sulfide. Butyl ,Butyric Acid, Pyridine

Weak Odors have Spray Glue, Dry Erase Markers, Paint cleaners. Water.

5 0

1 year ago

A quantity of 85.0 mL of 0.900 M HCl is mixed with 85.0 mL of 0.900 M KOH in a constantpressure calorimeter that has a heat capa

bogdanovich [222]

Explanation:

The given data is as follows.

$V_{1}$ = 85.0 ml, $M_{1}$ = 0.9 M

$V_{2}$ = 85.0 ml, $M_{1}$ = 0.9 M

Hence, number of moles of HCl and KOH will be the same because both the solutions have same volume and molarity.

So, No. of moles = Molarity × Volume

= $0.9 M \times 0.085 L$ (as 1 L = 1000 ml so, 85 ml = 0.085 L)

= 0.076 mol

As 1 mole gives 56.2 kJ/mol of heat of neutralization. Hence, calculate the heat of neutralization given by 0.076 moles as follows.

$56.2 kJ/mol \times 0.076 mol$

= 4.271 kJ

or, = 4271 J (as 1 kJ = 1000 J)

Therefore, heat released = - heat of gained by calorimeter

Since, it is given that density of the solution is similar to the density of water which is 1 g/ml.

Hence, mass of HCl = density × Volume of HCl

= 1.00 g/ml × 85.0 ml

= 85 g

Similarly, mass of KOH = = density × Volume of HCl

= 1.00 g/ml × 85.0 ml

= 85 g

Hence, total mass of the solution = 85 g + 85 g

= 170 g

Also, q = $mC \Delta T$

4271 J = $170 g \times 325 J/^{o}C \times (T_{f} - 18.24)^{o}C$

0.0773 = $T_{f} - 18.24$

$T_{f}$ = $18.317^{o}C$

Thus, we can conclude that final temperature of the mixed solution is $18.317^{o}C$ .

6 0

2 years ago

A mutation in the gene coding for a single-polypeptide enzyme results in the substitution of the amino acid serine, which has a

Alik [6]

Answer:

The correct answer is: The substitution altered the secondary and tertiary structure of the enzyme so that the mutated enzyme folds into a different shape than the normal enzyme does.

Explanation:

In the given condition, the substitution mutation of gene causes a replacement of serine by phenylalanine amino acids which causes a reduction in the activity of the enzyme. Since serine is polar and has -OH or hydroxy group involves the information of binding of biological catalyst to the substrate.

The primary structure of a protein is significant which finalizes the number of amino acids their sequence. The mutation of protein also affects both secondary and tertiary structures as it disturbs the structure of the protein and affects the catalytic activity as well as the binding affinity of the substrate.

the substitution of serin by phenylalanine does not affect or influence the mass of enzyme.

4 0

2 years ago

All of the following reactions can be described as displacement reactions except:____________.

Lady_Fox [76]

Answer:

Explanation:

The reaction that is not a displacement reaction from all the options is $C_6H_6_{(l)} + Cl_{2(g)} --> C_6H_5Cl_{(l)} + HCl_{(g)}$

In a displacement reaction, a part of one of the reactants is replaced by another reactant. In single displacement reactions, one of the reactants completely displaces and replaces part of another reactant. In double displacement reaction, cations and anions in the reactants switch partners to form products.

Options a, c, d, and e involves the displacement of a part of one of the reactants by another reactant while option b does not.

Correct option = b.

8 0

1 year ago