A few basic atomic problems are associated with the stopping of nonrelativistic pointlike ions in dense and hot matter. First, the free electron contribution is considered, taken in random phase approximation with an exact dynamic dielectric function, valid at any temperature. Stopping power and straggling can thus be obtained for any projectile velocity. The temperature dependence is of special relevance for a projectile energy <5 MeV/amu. The mean excitation energies of bound electrons are then considered and found to be smaller than in cold matter. The projectile effective charge in hot targets is also investigated. Experiments involving a heavy-ion beam produced by a standard accelerator and interacting with an independently produced coronal plasma are described.