The development of students' core competencies for the future society has become a shared goal in curriculum reform worldwide. Efforts are being made to investigate which core competencies should be cultivated and how they relate to the curriculum content. Specifically, designing core competency-oriented intended curriculum and translating it into implemented curriculum are common concerns and challenges encountered by countries during curriculum reform. In order to promote mutual sharing and learning among different countries and regions, the Organization for Economic Co-operation and Development (OECD) developed an analytical comparison framework and standards based on The Future of Education and Skills project. This study conducted a comparison between the 2011 edition and 2022 edition of the Compulsory Education Chemistry Curriculum Standards (CECCS) for students in grade 7 to grade 9. It identified 737 coding units for five learning themes and conducted a specific analysis and comparison using the Curriculum Content Mapping (CCM) and Theme Content Mapping (TCM). Heat maps are generated to reflect the correlation between China's grade 7 to grade 9 CECCS and the twenty-eight competencies identified in the OECD project, as well as the main emphasis before and after the revision of the curriculum standards. A mixed research method of qualitative and quantitative analysis was conducted to explore the characteristics of Chinese chemistry curriculum structure. This study provides insights into experiences regarding embodying core competencies, designing competency-oriented intended curriculum, and providing guidance for curriculum implementation in grade 7 to grade 9. It allows both teachers and educators to identify areas for improvement.