Place the atomic theories in the order in which they were published.

Atoms are made of empty space with electrons around a positively charged mass. The terms nucleus and proton (+) are introduced.

Negatively charged particles are called electrons and are scattered inside a positively charged mass.

Electrons exist in a region around the nucleus called the electron cloud.

Each type of matter is only made up of one type of atom. Atoms are too small to be seen.

Electrons are arranged in energy levels. Lower energy levels are close to the nucleus and higher energy levels are farther away from the nucleus.

What is the mass defect of a mole of nuclei with 1.8 x 10^15 j/mol binding energy?

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.

Achemist 16 drop copper metal from copper chloride solution. the chemist place is 0.50 g of aluminum foil in a solution containing 0.75 g of copper (ii) chloride. a single replacement reaction takes place. which statement explains the maximum amount of copper that the chemist can extract using this reaction?