Answer:
The nuclear charge increases, but the number of inner shielding electrons stays the same.
Explanation:
Their shielding does not change, so the effective nuclear charge — the charge felt by a valence electron — increases.
The valence electrons are pulled closer to the nucleus, decreasing the atomic radius.
For example, consider the elements of Period 3.

The number of protons increases as you go from one element to the next, but the number of inner electrons is constant.
Answer:
2:1
hydrogen is 2 and Oxygen is one
<h2>Answer:</h2>
A.NH4Cl
<h2>Explanations:</h2><h2>How are buffer formed?</h2>
Buffers are formed by mixing an equal amount of weak base or acids and their corresponding salts.
Therefore in order to make a buffer with NH3 (a weak base), then a corresposding weak salt is required. A corresponding salt for the given base is NH4Cl
basis for defining boundaries in the geologic time scale and for the correlation of strata.