Which best compares and contrasts how john newlands and dmitri mendeleev organized elements? both newlands and mendeleev arranged elements according to their chemical properties, but only newlands used atomic mass as well. both newlands and mendeleev arranged elements according to their atomic masses, but only mendeleev used chemical properties as well. both newlands and mendeleev organized elements into groups, but only newlands used a table with rows and columns. both newlands and mendeleev organized elements into a table with rows and columns, but only mendeleev named different groups of elements.

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead

The scheme below is from a series of reactions that are part of a synthesis of vitamin a. answer the following questions with reference to this scheme. (i) what is "reagent a"? (ii) draw a step-by-step mechanism which explains the formation of compound c from compound b (iii) which reagents would you use to form compound e from compounds c and d (reagents b and c)? for each reagent suggested above in (ii) explain the role of the reagent in the reaction to (iv) form compound e. you may wish to do this by drawing a mechanism. 1. addition of reagent a но reagent a 2. н,о" thо oh нон-с compound a. compound b. compound c .ch-оh 1. reagent b "сно 2. reagent c сh oh compound e. compound d.

Apiece of metal with a length of 1.42 cm was measured using four different instruments. which of the following measurements is the most accurate?