What is the significance of Plato’s problem of “saving the appearances” to the scientific mindset of the philosophers and Differentiate geocentric from heliocentric model of the universe.

If it started with Plato or a little later, the job for Greek Astronomers employed as the platonic tradition was, correctly or incorrectly, to save appearances: obviously to describe, in a mixture of uniform circular motions, irregular motion observed by senses.

Explanation:

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

14 days is the half-life of phosphorus-32