6. electrical fires cannot be safely put out by dousing them with water. however, fire extinguishers that spray solid carbon dioxide on the fire work very effectively. this method works because carbon dioxide..
answer: displaces the oxygen
7.when a metal is heated in a flame, the flame has a distinctive color, this information was eventually extended to the study of stars because..
Answer: the color specta of stars indicate which elements are present.
8. which statement best describes the density of an atom's nucleus?
Answer: the nucleus occupies very little of the atom's volume but contains most of its mass.
9. why are enormous amounts of enerygy required to seperate a nuclues into its component protons and neutrons even though the protons in the nuclues reprel each other?
answer: the focres holding the nuclues together are much stronger than the repulsion betweeen the protons.
2007-04-08 09:29:30 · 3 answers · asked by Simon W 1 in Science & Mathematics ➔ Chemistry
NOTE: THESE ARE QUESTIONS I GOT WRONG ON THE PRACTICE TEST FOR STAR 9. I DIDNT COPY.
2007-04-08 09:53:00 · update #1
6.Electric fires are the result of an electric arc. CO2 cools the arc to the point where the vaporization which supports the arc cannot take place. Unless the electricity can jump the gap to restart the arc, the fire goes out.
7. Not sure why you got this one wrong. Must be something in the wording or the failure to tie in the specra with compensation for the red shift due to the direction of the motion.
2007-04-09 12:21:47 · answer #1 · answered by Brian T 6 · 0⤊ 0⤋
Catalyst position molecules...........=true e.g. enzymes. Enzymes at their required temperature and Ph level forms necessary shape needed to digest a substance in the stomach. Examples of enzymes are: Pepsin, amylase, e.t.c Answer: the rate decreases. Reasons: At a high temperature, a reaction is more catalysed. According to Charles' Law and Gay-Lussac's Law, "When the number of particles are constant, the volume and pressure of an ideal behaving gas is directly proportional to its temperature." Therefore, dropping the pressure of the system to 0.5 atm will affect the reaction rate through its temperature.
2016-04-01 03:58:36 · answer #2 · answered by Anonymous · 0⤊ 0⤋
All of these answers are correct. It would take pages to explain them all.
Do some HW and you will get there
2007-04-08 09:32:53 · answer #3 · answered by reb1240 7 · 0⤊ 0⤋