A saturated solution of NH4CL was prepared in 100 g H2O. When the solution is cooled from 40 to 20°C, how many grams of precipitate formed

Aglow stick contains a glass vial with chemicals. when the glow stick is bent, the vial breaks and the chemicals react to produce a glow. a science student observes that a glow stick kept in the freezer glows for a longer duration than a glow stick kept at room temperature. what conclusion can be drawn based on the observation? be sure to note the outcome and test variables in the conclusion.

Which change to the system wood cause the freely-moving piston to lower?

What happens to the temperature of a substance when the average kinetic energy of its particles increases?