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
mote1985 [20]
3 years ago
14

Selenium (Se) has 30 protons and 20 neutrons in each atom, therefore its atomic

Chemistry
1 answer:
allochka39001 [22]3 years ago
8 0

Answer:

30, 50

Explanation:

Hello,

In this since an element's atomic number is equal to the number of protons in its atom, we can infer that selenium's atomic number is 30. Moreover, due to the fact the the neutrons are equal to the atomic mass minus the atomic number or the number of protons, by knowing the number of neutrons we compute the atomic as follows:

neutrons=mass-protons\\\\mass=neutrons+protons\\\\mass=30+20\\\\mass=50a.m.u

Thus, answer is 30, 50.

Best regards.

You might be interested in
In the process of attempting to characterize a substance, a chemist makes the following observations: (a) The substance is a sil
Amiraneli [1.4K]

The question is incomplete, this is the complete question;

In the process of attempting to characterize a substance, a chemist makes the following observations. Which are physical properties and which are chemical properties?

(a) The substance is a silvery white, lustrous metal.

(b) The substance melts at 649 ∘C

(c) The substance boils at 1105 ∘C.

(d) The density of the substance at 20 ∘C is 1.738 g/cm³.

(e) The substance burns in air, producing an intense white light.

(f) The substance reacts with chlorine to give a brittle white solid.

(g) The substance can be pounded into thin sheets or drawn into wires.

(h) The substance is a good conductor of electricity.

Answer:

(a) Physical

(b) Physical

(c) Physical

(d) Physical

(e) Chemical

(f) Chemical

(g) Physical

(h) Physical

Explanation:

(a) The substance is a silvery white, lustrous metal - is appearance which is physical.

(b) The substance melts at 649 ∘C metling point is a physical measurement

(c) The substance boils at 1105 ∘C boiling point is a physical measurement

(d) The density of the substance at 20 ∘C is 1.738 g/cm3 how heavy a substance is,is physical.

(e) The substance burns in air, producing an intense white light. Burning is a chemical change. It is a reaction of a substance with oxygen

(f) The substance reacts with chlorine to give a brittle white solid. This is a chemical reaction as the question says.

(g) The substance can be pounded into thin sheets or drawn into wires. Ductility is a physical change, the substance remains chemically unchanged

(h) The substance is a good conductor of electricity. Any conductivity is physical, the substance remains chemically unchanged

7 0
3 years ago
Which of the following is the best example of potential energy?
strojnjashka [21]
Answer :

A car stopped at the top of a hill

Explanation :

Definition of potential energy : energy stored that depends upon the relative position of various parts of a system
5 0
2 years ago
Which quantity will increase if the temperature is raised?
Irina-Kira [14]
OD.......................
4 0
3 years ago
Polar bonds share electrons _______.
Stells [14]
A polar bonds share electrons meaning they are a convenient bond
8 0
3 years ago
Give 2 reasons that tea is a mixture or solutions​
cricket20 [7]

Answer:

Tea is a solution of compounds in water, so it is not chemically pure.

Explanation:

It is usually separated from tea leaves by filtration. B Because the composition of the solution is uniform throughout, it is a homogeneous mixture.

4 0
2 years ago
Other questions:
  • 4. A total of 226 J of heat are absorbed as 58.3 g of lead is heated from 12.0oC to 42.0oC. From this data, what is the specific
    5·1 answer
  • According to the law of conservation of energy, the energy released by the system must be transferred to and absorbed by the sur
    9·1 answer
  • What is the SI unit of time?<br><br> Asecond<br> B. minute<br> C. hour<br> D. day
    10·1 answer
  • B) Name three substances which can undergo sublimation and deposition respectively​
    6·1 answer
  • Please do not write answer in a zip file
    11·1 answer
  • The shape of the illuminated portion of the Moon as seen by an observer, usually on Earth:
    13·1 answer
  • Why does buck ministerfullerene act as a good lubricant
    12·2 answers
  • Which structure is the arrow pointing to?<br><br><br><br> What is the function of this organelle?
    8·2 answers
  • Which electrophiles can react with an enol?
    13·1 answer
  • Calculate the number of grams nitric acid (HNO3) in 375 L of a 1.00 M solution.
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!