At a pressure of one billionth (10–9) of atmospheric pressure, there are about 2.7 × 1010 molecules in one cubic centimeter of a gas. how many molecules is this per cubic meter

Required answer =  2.7 x 10^16 MOLECULES

Explanation:

We know that

1 m = 100 cm

so 1 m^3 = (100 cm)^3 = 1000000 cm^3 = 1 x 10^6 cm3

as per question, 2.7*10^{10} molecules in 1 cm^3

so number of molecules in 1 m^3

Number of molecules = ( 2.7 x 10^10 molecules /1 cm^3 ) x ( 1 x 10^6 cm3 / 1 m3)

Number of molecules = 2.7 x 10^10 x 1 x 10^6 = 2.7 x 10^16 per m3

Required answer =  2.7 x 10^16 MOLECULES

an obstruction

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