<![CDATA[This research which aimed to describe the validity, teachers and students responses, and feasibility of student worksheets of vapor pressure depression and boiling point elevation of solution has been implemented by using RD method. Developed student worksheets were declared valid by the judgement in content suitability, construction, and legibility aspect 97.22%, 100%, and 100%, respectively, with very high criteria. On preliminary field testing, the result was obtained by teachers and students responses which value of them were 95.47% dan 95.81%, respectively with very high criteria. Based on feasibility test, developed student worksheets worthy were declared by observer 83.36% and students responses in four which each of then were aspect 91.67%, 75.55%, 100%, and 83.33%, respectively, with high and very high criteria.Penelitian ini yang bertujuan untuk mendeskripsikan tingkat validitas, tanggapan guru dan siswa, serta uji keterlaksanaan LKS pada materi penuruan tekanan uap dan kenaikan titik didih larutan telah dilaksanakan dengan metode penelitian dan pengembangan (Research and Development). LKS dinyatakan valid oleh validator pada aspek kesesuaian isi, konstruksi, dan keterbacaan berturut-turut 97,22%, 100%, dan 100% dengan kriteria sangat tinggi. Pada uji coba secara terbatas diperoleh hasil dari responden guru dan siswa berturut-turut 95,47% dan 95,81% dengan kriteria sangat tinggi. Berdasarkan hasil uji keterlaksanaan, LKS dinyatakan layak digunakan dalam pembelajaran oleh observer sebesar 83,36% dan responden siswa dalam empat aspek berturut-turut 91,67%, 75,55%, 100%, dan 83,33% dengan kriteria sangat tinggi dan tinggi.Kata kunci: discovery learning, kenaikan titik didih larutan, LKS, penurunan tekanan uap]]>
