Afew pieces of dry ice, co2(s), at -78°c are placed in a flask that contains air at 21°c. the flask is sealed by placing an uninflated balloon over the mouth of the flask. as the balloon inflates, the dry ice disappears and no liquid is observed in the flask.

80 state the direction of heat flow that occurs between the dry ice and the air in the flask.
81 write the name of the process that occurs as the dry ice undergoes a phase change in the flask. [1]
82 compare the entropy of the co2 molecules in the dry ice to the entropy of the co2 molecules in the inflated balloon.

This drawing shows a human body system. what is the primary function of this body system?

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.

Answer asap need by wednesday morning explain how a buffer works, using an ethanoic acid/sodium ethanoate system including how the system resists changes in ph upon addition of a small amount of base and upon addition of a small amount of acid respectively. include the following calculations in your i. calculate the ph of a solution made by mixing 25cm3 0.1m ch3cooh and 40cm3 0.1m ch3coo-na+. [ka = 1.74 x 10-5 m] ii. calculate the ph following the addition of a 10cm3 portion of 0.08 m naoh to 500cm3 of this buffer solution. iii. calculate the ph following the addition of a 10cm3 portion of 0.08 m hcl to 200cm3 of the original buffer solution.