Answer:
the fourth one or the first, but I wouldn't say I'm completely sure.
Explanation:
So you see the triangle with the letters, look at what you're given. you have mass and volume solving for density. So you take the mass and divide it by the volume. 15.2/15.5 which your answer is 0.98 or 1.0 that's your density.
Mass % of NaOH solution = 10 % (m/v)
Mass of NaOH required to prepare 1 L solution:

= 100 g NaOH
Answer:
filter the hot mixture.
Explanation:
Solid is stayed undissolved since the arrangement is gotten super saturated. On the off chance that solid molecule is available recrysallization won't happen in this way we need expel the solid molecule by filtarion in hot condition itself . Subsequently, arrangement become totally homogenous and recrysallization item will shaped by moderate cooling