Which type of property cannot be seen just by observing with the senses

What is the polyatamic ion of borate

He table below gives the atomic mass and relative abundance values for the three isotopes of element m. relative abundance (%) atomic mass (amu) 78.99 23.9850 10.00 24.9858 11.01 25.9826 what is the average atomic mass (in amu) of element m? 2.86 5.36 24.30 24.98

How many atomic mass units are equal to 1.672×10−24 g of protons?