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In titration we usually take burette reading upto $0.01~\mathrm{mL}$, but my teacher says that we need to take reading up to $0.05~\mathrm{mL}$. What does that mean? Does it mean if I read $23.56~\mathrm{mL}$ that I should record it as $23.60~\mathrm{mL}$ and if I read $23.44~\mathrm{mL}$ I should record it as $23.40~\mathrm{mL}$?

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I believe what your teacher means by this is that the error for your measurement is within $0.05~\mathrm{mL}$ of the estimate, since $0.05~\mathrm{mL}$ is half the value of the smallest measurable volume in a typical $50~\mathrm{mL}$ burette. This is typically how the error of an instrument reading is determined.

The readings you gave would then be: $23.56~\mathrm{mL} \pm 0.05~\mathrm{mL}$ and $23.44~\mathrm{mL} \pm 0.05~\mathrm{mL}$.

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  • $\begingroup$ Note:Just answering after my practical examination.99% of the time,the meniscus was on XX.05 or XX.00.It was just humanly impossible to even guess the meniscus position further than that without a magnifying glass.I think the burette was made in such a way that the individual drops were about 0.05 cm^3.So my readings were always XX.05 or XX.00. They were not lets say XX.69 or XX.67 or XX.63.Humanly impossible. $\endgroup$ – Irtiza May 7 '15 at 14:53

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