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  • Thank you for reporting this Helena. It is corrected now.
  • 17 April 2024
    Helena Van Lindert
    Significant figures and scientific notation
    Dear Geoffrey, I noticed the following on the handout sheet: 1.0476 (Zero is a significant figure - value quoted to 4 sig. figs)  ---<-------1.4760 (Zero is a significant figure - value quoted to 5 sig. figs)
  • 17 April 2024
    Vinaya Jaydev
    2014 DP Chemistry (Last exam Nov 24)
    Thanks Mr. Geoffrey - I had this confusion because  of the  observation at the cathode -  the  appearance of Grey metal at cathode (   during Pb Br2)or pinkish metallic solid ( during CuCl2). So the metal ions...
  • 16 April 2024
    Geoffrey Neuss
    2014 DP Chemistry (Last exam Nov 24)
    Hi Vinaya, I assume you mean the products of the electrolysis of molten sodium chloride? Sodium chloride melts at 801 oC. The melting point of sodium is 97.79 oC and the boiling point of sodium is 882.9 oC (see Section 8 of the 2023 IB data...