How long will it take for 500.0g of radium decay to 2.0g

How does electronegativity changes as we move from left to right across a period

The three sub fields of forensic entomologists

Which of the following characteristics are true about a typical peptide (amide) bond? the bond is planar. there is free rotation about the carbonyl carbon and nitrogen bond. there is substantial double-bond character to this bond. there is a net negative charge on nitrogen and net positive charge on oxygen.