<span>the noble gases are those who occupy the eighth group of the periodic table and are so called because having the complete valence shell do not need to form bonds with other atoms and are thus in atomic form ...
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The noble gases (also called rare gases) are of the inert gases that constitute the eighteenth [1] group of the periodic table of the elements, ie, the right-most column. They consist of atoms with electron shells full. It includes the following elements: helium neon argon krypton xenon radon Ununoctium <span>Sometimes they (particularly helium) are located together with other gases (mostly nitrogen and methane) into endogenous sources; helium of endogenous origin comes from the decomposition of radioactive elements present in the subsurface that emit α particles (ie ions He2 +): These oxidized species present in the soil and become elio.I atoms of the noble gases are all monatomic gas, not easily liquefiable, present the atmosphere in different percentages; the most common is argon which is approximately the 0.932%.</span>
<em>Answer: </em>John Dalton
Explanation: Democritus was a Greek philosopher (470-380 B.C.) who is the father of modern atomic thought. He proposed that matter could NOT be divided into smaller pieces forever. John Dalton created the very first atomic theory.
Answer:
If this trend continues, the following week will be cooler, and a large amount of rain will fall.
Explanation:
Patterns and trends can often be found in data sets. During the week that Cho recorded the weather, the temperatures consistently dropped by one to four degrees each day. At the end of the week, the amount of precipitation increased daily.
Meteorologists also use satellites to observe cloud patterns around the world, and radar is used to measure precipitation. All of this data is then plugged into super computers, which use numerical forecast equations to create forecast models of the atmosphere.
Answer: 24.1%, under below assumptions.
Justification:
The question is quite ambiguous, because one of the data is not clearly stated. It says that the mixture consists on two compounds:
- sodium bicarbonate, and
- ammonium bicarbonate
.After, it says that it is 75.9 % bicarbonate, but it does not specify which bicarbonate, it might be the sodium bicarbonate or the ammonium bicarbonate. It is apparent that you omitted that information by error.
Given that later, the question is <span>what the mass percent of sodium bicarbonate is in the mixture, it is supposed that the 75.9% content is of ammonium bicarbonate.
With that said, you can calculate the mass percent of sodium bicarbonate, because there are only two compounds and so you know that both add up the 100% of the mixture.
In formulas:
100% = %m/m sodium bicarbonate + %m/m ammonium bicarbonate = 100%
=> % m/m sodium bicarbonate = 100% - % m/s ammonium bicarbonate
=> % sodium bicarbonate = 100% - 75.9% = 24.1%
Answer: 24.1%
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