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When determining the melting point of an unknown substance, it is a common practice to first...

When determining the melting point of an unknown substance, it is a common practice to first determine a rough melting point by quickly heating the sample followed by a careful determination of the melting point by gradually heating the sample at the rate of 1-2 C /min. What is the advantage of this two-step determine of the melting point?

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Answer ) The advantage of this two-step determine of the melting point

1)well  the first step is known as approximate range analysis.

in this step we rapidly increase the heat and when our solid component starts to melt we note the point that will provide us the approximate range .

we use this information for our 2nd step determination of temperature.

2) In the second step, we , we start with the temperature that is let us say 30 degrees less than the value of Tm and then slowly increase the temperature ann with the increase of temperature slowly we can easily find the melting point of solid with much higher accuracy.

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