Test tube of ammonium chloride (NH4Cl) being heated over a bunsen burner flame. Ammonium chloride decomposes readily when heated, but condenses in the cooler area at the top of the test tube. This is a reversible reaction, where the ammonium chloride decomposes into the gases ammonia (NH3) and hydrogen chloride (HCl).
Answer:
The International Date Line, established in 1884, passes through the mid-Pacific Ocean and roughly follows a 180 degrees longitude north-south line on the Earth. It is located halfway round the world from the prime meridian—the zero degrees longitude established in Greenwich, England, in 1852.
Answer:
The concentration of the analyte is determined by fitting the absorbance or transmittance obtained by spectrophotometric analysis of the unknown solution into the calibration curve.
Explanation:
In a calibration curve, the instrumental response (absorbance or transmittance), is plotted against the concentration of the analyte (the substance to be measured). The analyst is expected to prepare a series of standard solutions of the analyte within a range of solution concentrations close to the expected concentration of analyte in the unknown solution. The method of least squares may be used to determine the best fit of the line, thus, the concentration of the analyte. This method is only used for the determination of the concentration of coloured substances (spectrophotometry).
