To wash out any trace chemicals. These trace chemicals coul affect the titration result.
If the burette is clean ( from the lab. store), it will have been through the stores washing machine, so there may be trace solvents left behind.
Titration is used in heaps of industries. Its used in wineries, dairy farms, mining corporations, cleaning material manufaturers, juce makers, food makers, cosmetic industries, health industries, water plants, paint makers and heaps more. Pretty much any industry that relies on something that has a pH uses titration. Usually it's used as a way to make sure that somehting's pH is sutable for human consumption or for human to be close to. However, it is also used to make sure that products, such a cleaning products, remove bacteria. Cleaning products need to be slightly acidic for these products to work so they titrate to get the right molarity. Sum up, titration is used in pretty much everything. :) Hope that helps everyone.
conductance not only depends on number of ions in solution but also depends on mobility of ions.if temperature increases then this electrical energy converts to heat energy due to this ions starts vibrate at their equilibrium position and they start moving to other place leads to more conductivity