Define international system of units , where does the system originate

The International System of Units (SI) is originated in France by frenches and originally was called a metric system of measurements. It provides definitions of various units of measurement such as weight, distance, electric current, temperature, and others which is widely accepted in the different fields of science and technology.

It is the system that is extended and derived from the french metric system of measurement is accepted in 1960 by convention 44 nation of the world to use particular unit of measurement worldwide to avoid confusion.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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