Answer:
All of the above.
Explanation:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.
This process is not reversible and a change of energy that is sometimes heat is given off.
Answer is ₂₀⁴²Ca.<span>
In AZX notation
A<span> - Represents the </span>mass number of atom.
Mass number = number of
protons + number of neutrons.
<span> It is shown at
the </span>above of the left side<span> of the
atom.</span>
<span> Here it is </span>42.
<span> </span>Z - Represents the atomic number.<span>
Atomic number = number of protons.
</span><span>It is shown at the</span> bottom line of the left side of the atom.<span>
</span>Here it is 20.<span>
X - </span>Represents the symbol of the atom.<span>
<span> </span></span>Here</span> X is Ca.<span>
</span>
Answer: The answer is 1/4
Explanation:
C. the number of protons and neutrons an element has in its nucleus
Answer:
Brackett Series (n = 4)
Explanation:
The least energetic line of Hydrogen atom lies in <em>Brackett Series </em>when n = 4 because these are least energetic, have longer wavelengths and lies in Infrared region of spectrum. No traces of <em>Pfund series </em>are formed by H=atoms.