All categories

4 years ago

?

Chemistry

1 answer:

ASHA 777 [7]4 years ago

6 0

Because the 4s orbital is at a lower energy level.

The 4s orbital has a lower energy because it is more <em>penetrating</em> than a 3d orbital. A 4s electron can get closer the nucleus than a 3d electron, so it has a lower potential energy.

The other options are incorrect because they contradict the correct one.

You might be interested in

KNO3(s) --> K+(aq) + NO3-(aq)This reaction was carried out in a Styrofoam insulated calorimeter and the following data were r

nataly862011 [7]

Answer:

Equation correctly showing the heat of solution

$KNO_3(s)+35.2 kJ \rightarrow K^+(aq) + NO_{3}^-(aq)$

Explanation:

Mass of aqueous solution = m = 100 g

Specific heat of solution = c = 4.18 J/gºC

Change in temperature = $\Delta T=T_f-T_i$

ΔT = 21.6ºC - 30.0ºC = -8.4ºC

Heat lost by the solution = Q

$Q = mc\Delta T$

$Q=100 g\times 4.18 J/g^oC\times (-8.4^oC)$

Q = -3,511.2 J ≈ -3.51 kJ

Heat absorbed by potassium nitrate when solution in formed; Q'

Q' = -Q = 3.51 kJ

Moles of potassium nitrate , n= $\frac{10.1 g}{101 g/mol}=0.1 mol$

$KNO_3(s)\rightarrow K^+(aq) + NO_{3}^-(aq)$

The heat of solution =

$\frac{Q'}{n}=\frac{3.5112 kJ}{0.1 mol}=35.1 kJ/mol$

So, the equation correctly showing the heat of solution

$KNO_3(s)+35.2 kJ \rightarrow K^+(aq) + NO_{3}^-(aq)$

4 0

4 years ago

How many liters of 0.305 M K3PO4 solution are necessary to completely react with 187 mL of 0.0184 M NiCl2 according to the balan

Mashutka [201]

Answer:

6.55 mL of K₃PO₄ are required

Explanation:

We need to propose the reaction, in order to begin:

2K₃PO₄ (aq) + 3NiCl₂(aq) → Ni₃(PO₄)₂ (s) ↓ + 6KCl (aq)

Molarity = mol/L (Moles of solute that are contained in 1 L of solution.)

M = mol / volume(L). Let's find out the moles of chloride:

- We first convert the volume from mL to L → 187 mL . 1L / 1000mL = 0.187L

0.0184 M . 0.187L = 0.00344 moles of NiCl₂

Ratio is 3:2. Let's propose this rule of three:

3 moles of chloride react with 2 moles of phosphate

Then, 0.00344 moles of NiCl₂ will react with (0.00344 . 2) /3 = 0.00229 moles of K₃PO₄

M = mol / volume(L) → Volume(L) = mol/M

Volume(L) = 0.00229 mol / 0.350 M = 6.55×10⁻³L

We convert the volume from L to mL → 6.55×10⁻³L . 1000mL /1L = 6.55 mL

5 0

3 years ago

The English system is used as the International System of Measurement. Please select the best answer from the choices provided T

kicyunya [14]

FALSE

explanation: the English system of measurement is mainly only used in England. The metric system is the international system of measurement.

8 0

3 years ago

Read 2 more answers

A 20-liter container contains 2. 0 moles of oxygen at a pressure of 92 kpa. The average kinetic energy of translation of oxygen

Elodia [21]

The average kinetic energy of translation of oxygen molecules in the gas is 5.05 × 10⁻²¹

The given data is

n = 2

v = 20

P = 92

K.E = 3 / 2 KbT

= 3 / 2 PV / N

= 3 / 2 Pv / nNa

K.E = 3 / 2 × 9 × 1.013 × 10⁵ × 20 × 10⁻³ / 2 × 6.022 × 10²³

K. E = 5.05 × 10⁻²¹ J

<h3>Average kinetic energy</h3>

The average kinetic energy (K) is equal to one half of the mass of each gas molecule times the RMS speed squared

Hence, the average kinetic energy is 5.05 × 10⁻²¹ J

Learn more about the average kinetic energy on

brainly.com/question/3249165

#SPJ4

7 0

1 year ago

The chemical name for the compound formula NaCl is?

Mandarinka [93]

Answer:

The chemical name for the compound formula NaCl is sodium chloride.

7 0

4 years ago

Read 2 more answers