Answer:
See explanation below
Explanation:
3. Each atom has unique electron energy level when compared to other, when electron relaxes from an excited energy level, it emits energy in the form of electromagnetic waves with energy equals to the difference between energy of ground and excited state. As electromagnetic wave wavelength obeys planck relation

And the energy of each photon in electromangetic wave of specific frequency is

Where h is planck's constant
We can see that the wavelength, which determines color and position of bright line in spectroscope corresponds directly to the energy of electromagnetic wave, and thus, the characteristic energy of atom.
4. From the answer above, you now know that electronic transition can emit electron with specific wavelength. In strontium, emission of colored light occurs by the relaxation of electrons in excited state such that the difference between excited energy level and ground level falls in the energy of visible light spectral range.
5. In Na, ground state configuration is 2-8-1. 2-7-1-1 indicates that one of electron in ground state got excited by external energy to excited state, and thus, indicates that Na atom is in excited state
C is not an example.
explanation: Mass is a physical property as the law of conservation of mass states mass is neither created nor destroyed in a chemical reaction or physical transformation. Chemical reactions are a change in the molecular structure of the product.
Answer:
It is a right triangle
Explanation:
We are given the directions in which a bird flew to make a triangle.
We are required to determine whether the triangle is right angle.
What is a right triangle?
- It is a triangle that has a right angle between the shorter sides or legs
- The triangle also obeys the Pythagoras theorem, such that the square of the two legs is equal to the square of the hypotenuse.
- Such that if the two legs are, a and b while c is the hypotenuse.
Then, a² + b² = c²
In this case;
Taking the legs as a= 21 yards and b = 72 yards and the hypotenuse, c = 75 yards.
Then we can determine whether it is a right triangle;
a² = 21² = 441
b²= 72² = 5184
c² = 75² = 5625
a² + b² = 5625
Therefore; a² + b² = c²
Hence, the triangle is right triangle.
Explanation:
Given a food with a relative humidity of 81%, what is the water activity of that food?
The water activity of a food can be determined by using the formula:
water activity=relative humidity of food / 100

Answer:
Option O = H₂O
Explanation:
Chemical reaction:
2K + 2H₂O → 2KOH + H₂
In this balanced chemical equation we can see that water is the only compound that consist of two hydrogen atom and one oxygen atom. H : O
2 : 1 .
In case of KOH two hydroxyl and two potassium atom are present and ration is K:OH 1:1.