When water vapor is cooled from 250°c to 150°c in a rigid tank the vapor just starts to?

What is the first element of the periodic table

How are large polymers formed? by repetitive combinations of simple subunits by the addition of halogens to a small molecule by combining a few different and larger molecules by combining many different and smaller molecules

Places rich in limestone and gypsum have hard water. Why?

Two fossils with reptilian characteristics are part of a shipment of fossils sent to a museum. The only difference is that one of the fossils shows evidence that the organism had feathers. Which fossil is probably older and why?

What is the systematic name of the following compound? CaF2

What is the rough er connected to

Two students design an experiment to see if pushing or pulling a box across the floor is more effective. The first student pushes the box across the floor a distance of 20 feet and the second student times how long it takes.

15.00 g of NH4HS (s) is introduced into a 500. mL flask at 25 °C, the flask is sealed, and the system is allowed to reach equilibrium. What is the partial pressure of ammonia in this flask if Kp = 0.108 at 25 °C for: NH4HS (s) ⇄ NH3 (g) + H2S (g) ?

Among elements 1-18, which element or elements have the smallest effective nuclear charge if we use the equation zeff=z-s to calculate zeff? check all that apply.

Two clear solutions are placed in separate beakers. The first solution has a pH of 4, and the pH of the second solution is unknown. If the two solutions are mixed and the resulting pH is 5, the second solution must have