In scientific notation, a number is less than ten but more than one.
Move the decimal point from 0, 250.000 <- this is the same as 250 to between 2 and 5.
I had to move two spaces.
2.5^2
I hope this helps!
~kaikers
Answer:
He developed the concept of concentric electron energy levels
Explanation:
Before Bohr's model, Rutherford's model was proposed. This model explains most of the properties of the atom but failed to explain the stability of the atom.
As per Rutherford's model, electrons revolve around the nucleus in the orbit.
But revolving electron in their orbit around nucleus would give up energy and so gradually move towards the nucleus and therefore, eventually collapse.
Bohr's proposed that the electrons around the nucleus move orbit of fixed energy called "stationary states". Electrons in these stationary states do not radiate energy.
Therefore, proposal of concentric electron energy levels refine the atomic models.
Answer: Option (d) is the correct answer.
Explanation:
In winter's, temperature of atmosphere is low and due to this molecules of air present in the tire come closer to each other as they gain potential energy and loses kinetic energy.
Hence, air pressure decreases and there is need to fill more air in the tire.
Whereas is summer's, temperature is high so, molecules of air inside the tire gain kinetic energy and move rapidly from one place to another due to number of collisions. So, air pressure increases and there is no need to fill more air inside the tire.
Thus, we can conclude that the temperature is lower, so the air inside the tires contracts.
A) Fe⁰ ----> Fe⁺³ +3e⁻ oxidation | *2
b) <u>Cu⁺² + 2e⁻ -----> Cu⁰ reduction |*3</u>
c) 2Fe⁰ +3Cu⁺² -----> 2Fe⁺³ + 2Cu⁰
Answer:
B) All carbon atoms have 6 neutrons.
Explanation:
The false statement from the given choices is that all carbon atoms have 6 neutrons.
There is a phenomenon called isotopy in chemistry.
Isotopy is the existence of two or more atoms of the same element having the same atomic number but different mass numbers due to the differences in the number of neutrons in their various nuclei.
- These atoms of elements are called isotopes.
- Carbon atoms generally have proton number of 6 which is the same as the atomic number.
- As with all atoms, the mass number or atomic mass equals the number of protons and neutrons.
For the isotopes of carbon, their number of neutrons differs.
For example:
<em>¹²₆C ¹³₆C ¹⁴₆C</em>
The number of neutrons differs in the above isotopes.
Number of neutrons = mass number - atomic number;
¹²₆C , number of neutrons = 12 - 6 = 6
¹³₆C, number of neutrons = 13 - 6 = 7
¹⁴₆C, number of neutrons = 14 - 6 = 8
Therefore, based on the concept of isotopy, all carbon atoms do not have 6 neutrons.
