a.
Formula used to convert temperature from °C to K = T(°C) + 273
Therefore, 23 °C => T (K) = 23 °C + 273 = 296 K
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b. According to the data provided:
At 23 °C => 85.0 g NaNO3 (s) are dissolved in 100. g water (l)
Curve G: Solubility curves show how changing the temperature changes the solubility of particles in a solvent.
From "y" axis Solubility => S = 90 g/100 g H2O approx.
The red curve on the drawing above shows the maximum amount of NaNO3 that we can dissolve in water.
The exercise says that we have 85 g/100 gH2O, but this is not saturated, we need 5 g more to get a saturated solution
Answer:
a. T = 296 K
b. 5 g more