How many molecules are in 200.0 g of ammonium sulfide

Which statement describes the appearance of a temperature-vs.-time graph? a horizontal line shows that the temperature increases at a constant rate over time. a vertical line shows that the temperature decreases at a constant rate over time. horizontal lines where the temperature is constant during phase changes connect upward-sloping lines where the temperature increases. horizontal lines where the temperature increases are connected by upward-sloping lines where the temperature is constant for each phase.

Which of these properties, used alone, would be least useful in identifying most minerals? a. color b. luster c. streak d. density

An electrons position cannot be known precisely only it's probability of being in a certain location can be known