  The 5-qubit quantum computer prototypes that IBM has given open access to on
the cloud allow the implementation of real experiments on a quantum processor.
We present the results obtained in five experimental tests performed on these
computers: dense coding, quantum Fourier transforms, Bell's inequality,
Mermin's inequalities (up to $n=5$) and the construction of the prime state
$|p_3\rangle$. These results serve to assess the functioning of the IBM 5Q
chips.
