Physics - Study Mode
[#526] The combined gas law relates which of the following?
Correct Answer
(D) Volume, Temperature & Pressure
Explanation
Solution: The combined gas law allows you to derive any of the relationships needed by combining all of the changeable pieces in the ideal gas law: namely pressure, temperature and volume.
[#527] The primary agent of contact metamorphism is
Correct Answer
(A) Temperature
Explanation
Solution: The primary agent of contact metamorphism is temperature.
[#528] In heating frozen foods in sealed pouches in a microwaves, why do you first poke holes in the pouch?
Correct Answer
(A) To prevent the steam pressure from bursting open the pouch
Explanation
Solution: Anything in a tight skin or shell can explode in a microwave because the water inside can expand and burst through. It is for this very reason that before microwaving, the skin of potatoes should be pricked, winter squash and similar vegetables should be cut in half, eggs should be taken out of shells and holes should be poked in the plastic wrap or sealed pouches of frozen packaged foods.
[#529] When two ice cubes are pressed together, they join to form one cube. Which one of the following helps to hold them together?
Correct Answer
(A) Hydrogen bond formation
Explanation
Solution: When two ice cubes are pressed together, they join to form one cube due to hydrogen bond.
[#530] A real gas can act as an ideal gas in
Correct Answer
(B) Low pressure and high temperature
Explanation
Solution: Real gases approximate ideal gases when their pressure is relatively low, and their temperature reasonably high. A real gas deviates increasingly from ideality as it is compressed and cooled to near the point at which it will condense into a liquid. Compressing forces the molecules closer together so that intermolecular forces become stronger, and cooling reduces the kinetic energy of the molecules, so that they are more easily held by these forces.