In order to understand why some combinations of alkyl halides and nucleophiles give a substitution reaction, whereas other combinations give elimination, and still others give no observable reaction, we must investigate systematically the way in which changes in reaction variables perturb the course of the reaction.
It's true - the ISS moves at about 17,000 mph (~28,000 kph). Now for your other questions: 1. When it's not using its onboard engines to adjust its orbit, the station is in free-fall*. This means that gravitational interaction with the earth maintains the station's orbit, and thus its speed.
However, a more typical altitude on a Shuttle flight is around 185 miles (300 km). If we substitute that altitude into the equation we have derived for circular orbital velocity, we get a speed of about 7,725 m/s, or 17,285 mph. This speed is about what we should expect since the Shuttle typically orbits the Earth at about 17,500 mph (28,165 km/h).