1. True
2. Faluse
3 true
4 false
Hope these are correct
The right answer is A rapid temperature increase will give a melting point range that is too high.
The melting point is determined in a capillary tube. it means the temperature at which the substance is completely melted, indicated by the disappearance of the solid, will not differ by ± 4 ° C from the given value, unless otherwise indicated.
The following technique can be applied to determine the melting point:
Grind some amount of substance in a small mortar. Place in a vacuum desiccator containing silica gel or phosphorus pentoxide and allow to dry for 24 hours at room temperature (unless another method of drying is indicated in the test protocol) . Introduce the substance into a dry capillary tube 1 mm inside diameter to form a column about 3 mm high. Heat the melting device to a temperature 5 to 10 ° C below the expected melting temperature and adjust the heating so that the temperature of the enclosure rises by approximately 1 ° C per minute. Introduce the capillary tube containing the substance into the heated chamber and note the temperature at which the agglomerated substance becomes completely transparent; this temperature constitutes the melting point.
seems like she is pretty ticked at her grade cause mabye it sucked?
Mutation is the primary cause of all genetic variation. Mutation is important as the first step in evolution, as it produces a new sequence of DNA for a particular gene, producing a new allele. Recombination, through intragenic recombination, may also generate a new DNA sequence (a new allele) for a particular gene.
