Acknowledgement of prior students' conceptions by science teacher has proved a significant tool for effective science teaching/learning. So the major objective of this research study is to investigate students' alternative ideas (misconceptions) and to develop an understanding about the existence of high frequencies of alternative ideas among science students at secondary level. A random sample of 120 students of 10th class was selected to explore students understanding regarding the concept chemical bonding. Seven instances or non-instances in total about this concept were developed to explore student's misconceptions. Inter-rater reliability was used to determine the reliability of the instrument (IAI) through Cohan Kappa cross tab statistics. Content validity of the instrument was established by experts' judgemental procedures. On the whole high frequencies of alternative ideas and low frequencies of scientific responses were obtained from girls and boys. Although, there was found relatively high frequency of alternative ideas in boys than girls, but overall high proportion of alternative ideas both in girls and boys at secondary level pointed out a big challenge for science educationalist. Further, categorical analysis revealed five categories of alternative ideas. In these alternative ideas many responses were identified as self-centered/human-centered. Similarly, subjects used many scientific terms but explained them incorrectly. There were found three other categories of alternative ideas but comparatively less in numbers. It was notable that less number of scientific ideas could develop despite of teaching chemistry for two years through traditional textbook approach at secondary level.