Energy
Compare particle motion in a block of solid iodine, a vial of liquid iodine, and a container of iodine gas.
particles in the solid vibrate in place and are slow; in the liquid they move past one another at moderate speeds; in the gas they move freely and fastest
Convert −72°C to Kelvin
201.15 K
A 95 g sample of aluminum warms from 18°C to 240°C. c = 0.215 cal/(g·°C). How much heat was absorbed?
4,534 cal
Which has stronger particle attraction: a material with a high melting point or one with a low melting point?”
the one with the higher melting point has stronger particle attraction.
Convert 412 K to Celsius.
138.85°C
A 1,300 g block of tin warms from −120°C to 24°C. Gaining 10,108.8 cal.
What is 0.054 cal/g*K
Between neon (melting −249°C) and potassium (melting 64°C), which has stronger bonds?
potassium, because its much higher melting point indicates stronger attraction.
Convert 23°F to Celsius
What is: −5.0°C.
A 450 g chromium block at 1600°C cools to 52°C and warms water from 21°C to 52°C. Chromium c = 0.100 cal/(g·°C). Calculate the mass of the water.
2,247 g
A heater uses 1500 J. If 250 J is sound and 120 J is kinetic in moving air, how many joules are transferred as heat?”
What is: 1,130 J.
Convert 650 K to Fahrenheit
710.3°F
A 2,000 g sample of iron (c = 0.107) is placed into 600 g water at 14°C. Final temperature = 48°C. Find the initial temperature of the iron.”
143.3°C.
Convert 125.6 degrees F into Kelvin
325 K
A workshop’s 280 kg of air (c = 0.240 cal/g·K) warms from 15.0°C to 24.5°C. A heater delivered 850,000 cal. Calculate how much heat leaked to the surroundings
about 211,600 cal leaked.
(Air mass in g = 280,000 g; heat absorbed = 280,000·0.240·9.5 ≈ 638,400 cal; leaked = 850,000 − 638,400 = 211,600 cal.)