The atomic numbers of four element P,Q,R and S are 6, 10,12 and 17 respectively. Which two elements can combine to form a covalent compound? ... <看更多>

Therefore, going 4 blocks to the right will give us the atomic number = 10+4= 14. Example 2) 4th period : 17th group. The last element of period ... ... <看更多>