Educators cannot overlook the affect's potential for students' educational success. In this study, affective analogies are proposed as a didactic resource to foster students' affect for chemistry learning and positive attitudes towards the physics-chemistry subject. To examine the influence of the affective analogies on it, we grouped contents of this subject into three modules (Kinetic-molecular theory; Quantum model of the atom; Chemical elements and their isotopes) and developed analogies between chemistry and music for each (affective analogies), which were then compared to homologous undifferentiated analogies (familiar analogues without affective qualities in addition) and teaching strategies without analogies. An explanatory mixed-method design was used. Data were collected through questionnaires and interviews, with a convenience sample of 147 students attending the 7th grade of a middle school music course. The results show that the affective dimension of analogies promotes positive affect for learning at much higher levels than the familiar dimension. We proposed a mechanism through which this occurs. However, if analogies are familiar, it seems that their positive affective dimension is not as important for students' learning levels. More than interesting, analogies should perhaps be non-aversive. As for attitudes towards physics-chemistry, teaching with affective analogies is the most beneficial strategy. This results from students' perception that this teaching approach promoted positive affect for the study of physics-chemistry, compared to undifferentiated analogies and without analogies. Furthermore, it favoured learning and achievement in physics-chemistry, compared to the absence of analogies, because without analogies it is more difficult to understand abstract or difficult concepts.