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.
<u>Answer:</u> The density of liquid is 
<u>Explanation:</u>
We are given:
Mass of cylinder,
= 65.1 g
Mass of liquid and cylinder combined, M = 120.5 g
Mass of liquid,
= 
To calculate density of a substance, we use the equation:

We are given:
Mass of liquid = 55.4 g
Volume of liquid = 49.3 mL =
(Conversion factor:
)
Putting values in above equation, we get:

Hence, the density of liquid is 
Explanation:
the volume and temperature of a gas have a ditect relationship,as the temperature increases the volume also increases when pressure is held constand, heating the gas increases the kinetic energy of the particles or atoms,causing the gas to expand until the pressure returns to its original value