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We present the results of a spectral-imaging analysis of X-ray data obtainedwith the Position Sensitive Proportional Counter aboard the ROSAT Observatoryin a 32 ks pointed observation of Hickson's Compact Group (HCG) #94. BesidesHCG94, A2572, a richness class 0 Abell cluster, is also contained in thecentral region of the field of view.  Both systems are at a redshift of z~0.04 and are falling toward each other ata velocity of about 1000 km/s. Their three-dimensional spatial separation isprobably of the order of an Abell radius; however, as yet, no clear signs ofdynamical interaction are discernible in the X-ray.  We find HCG94's gas temperature and unabsorbed X-ray luminosity to be far toohigh for a galaxy group thereby confirming the claim of Ebeling, Voges &B"ohringer (1994) that HCG94 should be classified as a galaxy cluster. Theopposite is true for the Abell cluster A2572, the optical richness of which hasbeen overestimated due to the inclusion of HCG94. In the X-ray, A2572 appearsat first sight like the prototypical binary cluster with two equally massiveand X-ray bright subclusters in the process of merging. However, the availableX-ray, optical, and radio data strongly suggest that A2572 proper is in factmerely a loose group of galaxies, while the second component is a much richerand more distant cluster seen in superposition.  A deprojection analysis shows HCG94 to host a moderate cooling flow; thispicture is supported by a radial increase in the column density of absorbingmaterial and a decrease in the gas temperature toward the cluster centre.HCG94's total gravitating mass is much higher than what could be anticipatedfrom its appearance in the optical. Our findings hence underline the need for

A 2572 and HCG 94 - galaxy clusters but not as we know them: an X-ray case study of optical misclassifications