Asample of barium nitrate is placed into a jar containing water. the mass of the barium nitrate sample is 27g. assume the water is at 20 degrees c and the resulting barium nitrate solution is saturated. what mass of water is present in the jar?

So we have Barium nitrate with a solubility of 8.7g in 100g water at 20°C.

using that relation
i.e.
8.7g (barium nitrate) =100g (water)
1g barium nitrate = 100/8.7 g water

27g barium nitrate = (100/ 8.7 ) × 27
= 310.34 g

therefore,
you need 310.34g of water is in the jar.

The answer to this is the 3rd choice!

Answer; carbon monoxide (co);