Using the phase diagram for CO2, what phase is carbon dioxide in at -20°C
and 1 atm pressure?
O
A. It is in the solid phase.
O
B. It is at its boiling point.
O
c. It is in the liquid phase.
D. It is in the gas phase.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? a. the balloons both rise. the cold balloon is larger than the warm balloon. b. the balloons rise at the same rate. both balloons are the same size. c. the warm balloon expands and rises. the cold balloon shrinks and sinks. d. the cold balloon expands and rises. the warm balloon shrinks and sinks.

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

Compare the valence electron configuration of the nobles gas elements seen here. what statement is correct?