Which statement is one of the three parts of cell theory? a) the smallest living things are single cells, and cells are the functional units of multicellular organisms. b) there are three types of cells, prokaryotic, eukaryotic plant, and eukaryotic animal. c) cells make up tissues, tissues make up organs, organs make up systems, systems make up organisms. d) cell organelles can be membrane-bound or not membrane-bound.

the correct answer is:

a. formation of precipitation

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2