A45.0l gas cylinder contains 988 he at 23 degrees c what is the pressure inside the cylinder

P = 133.4 atm

Explanation:

Given data:

Mass of helium = 988 g

Volume = 45.0 L

Temperature = 23°C (23+273= 296 K)

Pressure of cylinder = ?

Solution:

Number of moles of helium:

Number of moles = mass/ molar mass

Number of moles = 988 g/ 4 g/mol

Number of moles = 247 mol

Pressure:

PV = nRT

P = nRT/V

P = 247 mol × 0.0821. atm. L/mol. K × 296 K / 45 L

P = 6002.5 / 45 L

P = 133.4 atm

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year