The experimental procedure has you wash your thermometer and dry it after you measure the temperature of the acid and base solutions. how would your result be affected if you measure the temourature of th hcl solution and immediately ,easure the tempurature of the naoh solution without rinsing and drying the thermometer?
If you don't wash the thermometer, residual NaOH will react with the HCl solution. This is a highly exothermic reaction and will change the temperature of the solution, and thus throw off your measurement.
