How many diffrent elements are in the compound NaHCO3

Explanation:

baking soda, bread soda, bicarbonate of soda, and cooking soda.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

the answer is c

tell me if wrong