On the pH scale, where can you find strong acids and strong bases? A. On the left side of the pH scale
B. In the middle of the pH scale
C. On the right side of the pH scale
D. On either side of the pH scale

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

the answer is na (sodium)