calculating ppm in a room?

Question

I have to calculate the ppm that would be present in a room if a beaker of solution was spilled and then evapourated. I have the volume of substance, the molecular weight, the dimensions of the room it says i need to calculate the fractional volume/volume concentration in the lab then multiply by 10 to the power of 6 can anyone help me with this i'm tearing my hair out!!!

Answer 1

In this case you can simply derive ppm by dividing the volume of substance by the volume of the room, then multiplying that fraction by one million.....(ex: 1 cu-in of substance in a room that is 96-in x 240-in x 240-in is 0.18 ppm)

Answer 2

Let's do a for instance. The dimensions of our room are :-
length 5 metre, width 4 metre , height 3 metre.
The number of cubic centimetres in the room is 500*400*300 cc
Your beaker held 500 cc of the liquid before it was spilled: all of this ends up in the atmosphere of the room. So, it takes up 500/(500*400*300) part of the room and occupies 10^6*500/(500*400*300) ppm = 8.3333 ppm. of the atmosphere of the room.
You do not need the molecular weight information, because its volume/volume that we are concerned with here.

Answer 3

You need to find the ppm (parts per million) concentration by volume (not weight). This will be the parts of evaporated molecules in the room at standard pressure and temperature compared to all the parts in the room. I would consider that evaporation (to form a cube?) will displace some air from the room. So divide the cubic feet of vapor (from the beaker) by the total cubic feet of volume of the room to get the ratio of vapor to total volume. Multiply the ratio by 100 to get % or by 1,000,000 to get the fraction of one million parts (ppm).

Answer 4

Avogadro's Hypothesis states that gases at the same temperature and pressure simply have their # of molecules proportional to their volume. So just divide the volume of the gas by the volume of the room and multiply by a million.