1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ratelena [41]
2 years ago
11

Which element contains one set of paired and three unpaired electrons in its fourth and outer main energy level? ​

Chemistry
1 answer:
Natasha2012 [34]2 years ago
4 0

Explanation:

Phosphorus (P) because of the 5 valence electrons total, 3 of them are in the 3p sublevel, and according to Hund's rule, they "single-fill" each orbital first.

You might be interested in
An iron block of mass 18 kg is heated from 285 K to 318 K. If 267.3 kJ is required, what is the specific heat of iron? A. 450.00
valkas [14]

Answer:

  • <u>Option A. 450.00</u>

Explanation:

<u>1) Data:</u>

a) m = 18 kg

b) T₁ = 285 K

c) T₂ = 318 K

d) Q = 267.3 kJ

e) S = ?

<u>2) Principles and equations</u>

The specific heat of a substance is the amount of heat energy absorbed to increase the temperature of certain amount (gram, kg, or moles, depending on the definition or units) of the substance in 1 ° C or 1 K.

The mathematical relation between the specific heat and the heat energy absorbed is:

  • Q = m × S × ΔT

Where,

  • Q is the heat absorbed,
  • S is the specific heat, and
  • ΔT is the temperature increase (T₂ - T₁)

<u>3) Solution:</u>

<u>a) Substitute the data into the equation:</u>

  • 267.3 kJ = 18 kg × S × (318 K - 285 K)

<u>b) Solve for S and compute:</u>

  • S = 267.3 kJ / (18 kg × 33 K) = 0.45 kJ / (Kg . K)

The options have not units, but I notice that the first answer is 1,000 times the answer I obtained, so I will make a conversion of units.

<u>c) Convert to J /( kg . k):</u>

  • 0.45 kJ / (Kg . K) × 1,000 J / kJ = 450 J / (kg . K)

Now we can see that the option A is is the answer, assuming the units.

6 0
3 years ago
What would be the temperature of 0.6 moles of fluorine that occupy 15 L at 2,300 mmHg?
Anna [14]

Answer: The temperature of 0.6 moles of fluorine that occupy 15 L at 2,300 mmHg is 920 K

Explanation:

According to ideal gas equation:

PV=nRT

P = pressure of gas = 2300 mm Hg = 3.02 atm  (760mmHg=1atm)

V = Volume of gas = 15 L

n = number of moles = 0.6

R = gas constant =0.0821Latm/Kmol

T =temperature = ?

T=\frac{PV}{nR}

T=\frac{3.02atm\times 15L}{0.0821Latm/K mol\times 0.6mol}=920K

Thus the temperature of 0.6 moles of fluorine that occupy 15 L at 2,300 mmHg is 920 K

8 0
3 years ago
Chemistry screen shot below plzzzzzzz help i've been stuck forever
Oxana [17]

Answer:

True

Explanation: Imagine the Electrons is by the nucleus which give more energy.

8 0
2 years ago
Read 2 more answers
The NaCl crystal structure consists of alternating Na⁺ and Cl⁻ ions lying next to each other in three dimensions. If the Na⁺ rad
Yuliya22 [10]

Answer : The radii of the two ions Cl⁻ ion and Na⁺ ion is, 181 and 102 pm respectively.

Explanation :

As we are given that the Na⁺ radius is 56.4% of the Cl⁻ radius.

Let us assume that the radius of Cl⁻ be, (x) pm

So, the radius of Na⁺ = x\times \frac{56.4}{100}=(0.564x)pm

In the crystal structure of NaCl, 2 Cl⁻ ions present at the corner and 1 Na⁺ ion present at the edge of lattice.

Thus, the edge length is equal to the sum of 2 radius of Cl⁻ ion and 2 radius of Na⁺ ion.

Given:

Distance between Na⁺ nuclei = 566 pm

Thus, the relation will be:

2\times \text{Radius of }Cl^-+2\times \text{Radius of }Na^+=\text{Distance between }Na^+\text{ nuclei}

2\times x+2\times 0.564x=566

2x+1.128x=566

3.128x=566

x=180.9\approx 181pm

The radius of Cl⁻ ion = (x) pm = 181 pm

The radius of Na⁺ ion = (0.564x) pm = (0.564 × 181) pm =102.084 pm ≈ 102 pm

Thus, the radii of the two ions Cl⁻ ion and Na⁺ ion is, 181 and 102 pm respectively.

4 0
3 years ago
The number of positive changes in the nucleus of an atom is equal to
raketka [301]

Answer:

The number of positive charges in nucleus of an atoms are equal to the atomic number and also positive charges are equal to the negative charges which are electrons in neutral atom.

Explanation:

An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.

Electron:

The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.

Symbol= e⁻

Mass= 9.10938356×10⁻³¹ Kg

It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.

Neutron and proton:

Neutron and proton are present inside the nucleus. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.

Symbol of proton= P⁺

Symbol of neutron= n⁰

Mass of proton=1.672623×10⁻²⁷ Kg

Mass of neutron=1.674929×10⁻²⁷ Kg

All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.

For example

The carbon have six protons and six neutrons so its atomic mass is 12 amu and atomic number is six.

8 0
2 years ago
Other questions:
  • An atom had an average atomic mass of about 63.5 amu. What is the chemical symbol for the atom?
    14·1 answer
  • How many grams of H3PO4 are produced when 10.0 moles of water react with an excess of P4O10?
    6·1 answer
  • How many moles of sodium iodide are needed to remove 5.95×10−6 mol of o3?
    11·1 answer
  • What is the henry's law constant for co2 at 20∘c? express your answer to three significant figures and include the appropriate u
    11·2 answers
  • your skin is the largest organ of your body. The skin and its appendages, hair and nails, are known as the integumentary system.
    12·2 answers
  • Please help me with these I'll give 15 points
    13·2 answers
  • How many moles of calcium hydroxide, ca(oh)2, are needed to neutralize 2 moles of sulfuric acid, h2so4?
    5·1 answer
  • Toaster pops up knocks over ball what type of energy is that ?
    7·1 answer
  • HELP PLEASE I dont understand this (7th Grade science)
    9·2 answers
  • How to get pH from OH-
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!