ch10 review answers
What is the limiting reactant? hydrogen What mass of excess reactant is left over? 56g of nitrogen
standard molar volume is ___22.4_____L at __STP_____. 48g of methane (CH4) would occupy ___67.2__ L at Standard conditions and pressure.
29 If 20g of butane (C4H10) was mixed with an unlimited amount of oxygen and ignited what would be the limiting reactant? butane
What mass of water would result?
2C4H10 + 13 O2 = 8CO2 + 10H2O
20g but *1mol but/58gbut * 10mole water/2mol but * 18g water/1mol water = 31g water
What volume of carbon dioxide would result ?
20g but *1mol but/58gbut * 8mole carbon dioxide/2mol but * 22.4L carbon dioxide/1mole carbon dioxide = 31L CO2
What if the above reaction were done with 26g of butane and 96g of oxygen, what would be the limiting reactant?
26g but * 1mol but/58g but * 13mol ox/2mol but * 32g ox/1mol ox = 93.2 g ox; therefore butane is l.r.
What mass of water would result?
26g but *1mol but/58gbut * 10mole water/2mol but * 18g water/1mol water = 40.3g water
What volume of carbon dioxide would result ?
26g but *1mol but/58gbut * 8mole carbon dioxide/2mol but * 22.4L carbon dioxide/1mole carbon dioxide=40.2L CO2
How much excess reactant remains? 96-93.2= 2.8g oxygen
11-16 Using the graph below, find the triple pt T= .01 C, triple pt P = .006atm, normal mp= 0C,
normal bp= 100C, critical T = 374, critical P= 218atm note: It won't be water on the test, the points will not be labeled, and the dotted lines will not be there
In OUR LAB:
We heated water; once it reached ___100__degrees C its temperature did not go up, even when we were heating it. This is because the heat was being used to change __liquid__ to __gas__. When we plotted this information on a graph, we could see a ____plateau_______ that indicated the phase change. When water boils, the bubbles are water ___gas__. Many people think the bubbles are __hydrogen_______ and ______oxygen____; if that were true, it would be dangerous to boil water!
When we cooled water we used a salt and ice. Salt ___lowered_____ the melting pt of water; the salt ice mixture reached about ___-15_____ degrees C. When we put the test tube of water in this bath, the temp went down and the graph formed a __plateau_______ at _____0___ degrees C; this showed us the ____freezing_______ pt of water.
Paradiclorobenzene is a ___solid_____ at room conditions, but a _____liquid____ at 95 degrees C.
Its uses include ______deodorizer__________ and __________insect killer____________. The temperature went down the graph made a ____plateau______at ___53____degrees C; this showed us the ______freezing_______pt for paradiclorobenzene. Freezing point is always __equal_______ the Melting pt.
What does kinetic mean? Motion What is the main idea in kinetic theory? Atoms are always moving
What are some properties of gases that can be explained by kinetic theory? Diffuse, low density, compressible Use kinetic theory to explain these properties. Diffusion = always moving; low density = far apart particles ; compressible = far apart particles
Sketch an atomic view of a beaker with Iron metal and oxygen gas in it.
Explain how ice keeps drinks cool. Energy that would warm the drink to room temp is used to change solid to liquid
How does your body keep cool on a hot day? Why does it work so well? Sweat. Energy that could cause body temp to go too high is used to change liquid sweat into gas. It works so well because it takes a lot of energy
1-5 Using the graph above, indicate the Ti,-20 Tf 120 Bp, 100 mp, 0 fp 0
6-10 Using the graph above, indicate the state of matter found
a solid b solid to liquid c liquid d liquid to gas e gas
17 Is it possible to remove heat without temp decreasing? If so, give evidence. Yes, it happens at freezing pt. even though heat is being removed the temp stays the same until all the liquid is solid
18 Give an example of how heat of fusion (ice keeping drink cool)and vaporization( sweat evaporating ) is used everyday,
20 Given that the Hfus of water is 6Kj/mol and the Hvap of water is 41Kj/mole, would heat be added or removed to change 50g of ice to water? Energy must be added
21 (know: 6 phase changes*, compare s,l,g) What type of phase change is frost?* deposition
22 Which phase changes require energy to be added?
23 What is the most ordered phase?
24 What phase(s) is(are) fluid?
25- 15 match terms with statement: dynamic equilibrium, capillary action, amorphous, melting pt, boiling pt, hydrogen bonding, triple pt, critical temp, Le Chatlier’s principle, surface tension, heat of fusion & vaporization, crystal, sublimation, volatile
26 What does kinetic mean?
27 explain the properties of gases using kinetic theory
Ch10 review answers:
28 balance this equation. fill in the table
N2 + 3H2 => 2NH3