which phrase best describes a scientist? a. a person who is highly educated b. a person who learns about the world by observing it. c. a person who understands how the world behaves. d. a person who is extremely knowledgeable about the world

B

Explanation:

None of the other responses doesn't seem right. A is to broad someone can be a scientist and might not be highly educated. C not every scientist studies this field so no. Same goes for D

i don't know people like to fight everywhere rip.

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