Question

An expensive vacuum system can achieve a pressure as low as (1.00 X 10⁻12) atm at 0.0ºC. How many atoms are there in a cubic centimeter at this pressure and temperature?

a) (2.68 X 10¹9)
b) (6.02 X 10²3)
c) (1.67 X 10⁻11)
d) (1.00 X 10⁻12)

Answer 1

To find the number of atoms in a cc at 1.00 x 10-7 N/m² and 20°C, convert the pressure to atm, use the ideal gas law to calculate moles, and then multiply by Avogadro's number to get the total atoms.

Step-by-step explanation:

The question asks to calculate the number of atoms in a cubic centimeter (cc) at a certain pressure and temperature using the ideal gas law.

Given a pressure value of 1.00 x 10-7 N/m² and a temperature of 20°C, which is equivalent to 293 K (using the conversion from Celsius to Kelvin), we can find the number of atoms present.

First, we'll need to convert the pressure from N/m² to atmospheres (atm), because the standard volume of a mole of gas at STP is measured in liters and atmospheres.

Then, using the ideal gas law PV = nRT, we can solve for the number of moles n. After finding the number of moles, we convert moles to atoms using Avogadro's number (6.02 x 10²³ atoms/mol).

It's important to note that the actual calculation process requires further information or assumptions that are not provided here, such as the specific gas constant R value to use (which depends on the units of pressure).

However, the given multiple choice answers suggest that calculations of this kind have been performed.