Elements are organised in the <em>periodic</em> table of elements, which is essentially a big table that lists elements in order by increasing atomic number and atomic mass.
Each row of a periodic table is called a 'period', and when elements are arranged in the above-described way, there is a repeating pattern because each column has elements that share properties. So as you move across a period (or row), you get elements of different properties, but as you move across another period, you get different elements with similar properties as before.
Look up chromium on periodic table. It's atomic number is 24. It gives number of protons in an element. Since the atom is uncharged (no extra or subtracted electrons), the number of protons will equal the number of electrons.
CH is nonpolar NH is polar CCl is polar SiO is polar SCl is polar CO is polar OF is nonpolar Remember that polarity results from unequal electron sharing
