Tests for gases
Hydrogen, oxygen, carbon dioxide, ammonia and chlorine can be identified using different tests.
Hydrogen. A lighted wooden splint makes a popping sound in a test tube of hydrogen.
Oxygen. A glowing wooden splint relights in a test tube of oxygen.
Answer:
Na = 32.4% , % S = 22.6% and %O = 45.0%
Explanation:
% Na = 3.4/10.5. × 100%
= 32.4%
%S = 2.37/10.5 × 100%
= 22.6%
% O= 4.73/10.5 × 100%
= 45.0%xplanation:
Answer: Thus concentration of 
in 
is 0.011 and in 
is 0.814
Explanation:
To calculate the concentration of , we use the equation given by neutralization reaction:
where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is
We are given:
Putting values in above equation, we get:
The concentration in is 
Thus concentration of is 
and 
Answer:
- <em>He realized that some elements had not been discovered.</em>
Explanation:
Some scientists that tried to arrange the list of elements known before Mendeleev include Antoine Lavoisier, Johann Döbereiner, Alexandre Béguyer de Chancourtois, John Newlands, and Julius Lothar Meyer.
<em>Dimitri Mendeleev</em> was so succesful that he is recognized as the most important in such work.
Mendeleev by writing the properties of the elements on cards elaborated by him, and "playing" trying to order them, realized that, some properties regularly (periodically) repeated.
The elements were sorted in increasing atomic weight (which is not the actual order in the periodic table), but when an element did not meet the pattern discovered, he moved it to a position were its properties fitted.
The amazing creativity of Mendeleev led him to leave blanks for what he thought were places that should be occupied by elements yet undiscovered. More amazing is that he was able to predict the properties of some of those elements.
When years after some of the elements were discovered, the genius of Mendeleev was proven because the "new" elements had the properties predicted by him.
There is an excess of oxygen, the two main products should be carbon dioxide gas and water vapor. If the oxygen supply is limited, the fuel will undergo incomplete combustion and produce carbon monoxide, water, and sometimes carbon.
Hope this helped! :)
