Which statement best describes how electrons till orbitals in the penodic table? Electrons fill orbitals in order of their increasing energy from left to right
o Electrons fill orbitals in order of their increasing energy from right to left
Elements fill orbitals in order of increasing energy from top to bottom in each group
Elements fill orbitals in order of increasing energy from bottom to top in each group.

The pressure inside a hydrogen-filled container was 2.10 atm at 21 ? c. what would the pressure be if the container was heated to 92 ? c ?

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.

Which of these statements explains the difference between nuclear binding energy and the strong nuclear force ?