What mass of Ni(CO)4Ni(CO)4 is allowable in a laboratory that is 12 ftft ×× 21 ftft ××11 ftft ? Express your answer using two significant figures.

The answer to the question is

Only up to 1.45×10⁻³ grams of Ni(CO)₄ is allowable in the room

Explanation:

The allowable concentration of Ni(CO)₄ in a room is 1 ppb that is one part per billion, therefore

volume of gas in a room of 12 ft by 21 ft by 11 ft = 2772 ft³

From PV = nRT, n = (P×V)÷(R×T)

in SI units we have  at 1 atm or 101325 Pa, V = ‪78.49 m³   R 3.142 J/mol·K

n = 101325×78.49/(3.142×298.15) = 8489.65 moles

The room can contain 8489.65 moles of  Ni(CO)₄ However allowable concentration is 1 part per billion or

(8489.65/1000000000) moles = 8.49×10⁻⁶ moles

Molar mass of Ni(CO)₄ = 170.73 g/mol

Allowable mass of Ni(CO)₄ = Number of moles × molar mass

= 170.73 g/mol×8.49×10⁻⁶ moles = 1.45×10⁻³ grams

i just learnt this recently but i need to look through my notes again

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