Answer:
Element A = Oxygen
Element H = 
Element B = Aluminum
Element J = Magnesium
Element C = Selenium
Element L = Carbon
Element D = Sodium
Element Q = Francium
Element F = Antimony
Element R = Calcium
Element G = Chlorine
Element S = Tellurium
Explanation:
Element A  is Oxygen because: oxygen 6 valence electrons
; is a gas at room temperature
; and is transported in blood to cells.
Element H  is Neon because: Neon is a noble gas
;   qppears as red light when charged with  electricity (Neon light signs)  and it has the second highest Ionization energy of the elements
Element B  is Aluminum because: Aluminum is a metal and its ion has charge of +3. It is also located on the borders of the Metalloid staircase
.
Element J  is Magnesium because its ion has charge of 2+ and is  isoelectronic with Neon  because it loses two electrons to now have 10 electrons.
Element C  is Selenium because its ion that has a charge of -2  is formed by gaining two electrons in order to have 36 electrons which is isoelectronic with Kr
ypton
Element L  is Carbon because carbon has the smallest atomic radius of any member in the Carbon family  because it is the first member of the family and atomic radius increases on going down the group.
Element D  is Sodium because its ion has charge of +1  and it has 2 inner core levels
, the 1 and 2 energy levels.
Element Q  is Francium because it has the largest radius and lowest ionization  energy of any element
Element F  is Antimony. It is a member of Nitrogen family  and has the second highest ionization energy level in family
.
Element R  is calcium because its on has charge of +2  which is isoelectronic with Argon
. Calcium also has atomic radius is larger than Ar
gon.
Element G  is Chlorine. It has the second to the smallest radius of elements in the 3rd period  as the second to the last element in the period because atomic radius decreases across a period from left to right.
Element S  is Tellurium. It has atomic mass larger than Iodine just to the right  of it and is found in the 5th period
 
        
             
        
        
        
Answer:
chemical change
Explanation:
electrolysis process by which electric current is passed through a substance to effect a chemical change. 
 
        
             
        
        
        
The expectancy of how long a product will last divided by two!
        
             
        
        
        
<span>Answer:
From the ideal gas law, MM=mRTPV; where MM = molecular mass; m = mass; P = pressure in atmospheres; V= volume in litres; R = gas constant with appropriate units.
So, 0.800â‹…gĂ—0.0821â‹…Lâ‹…atmâ‹…Kâ’1â‹…molâ’1Ă—373â‹…K0.256â‹…LĂ—0.987â‹…atm = 97.0 gâ‹…molâ’1.
nĂ—(12.01+1.01+2Ă—35.45)â‹…gâ‹…molâ’1 = 97.0â‹…gâ‹…molâ’1.
Clearly, n = 1. And molecular formula = C2H2Cl2.
I seem to recall (but can't be bothered to look up) that vinylidene chloride, H2C=C(Cl)2 is a low boiling point gas, whereas the 1,2 dichloro species is a volatile liquid. At any rate we have supplied the molecular formula as required.</span>
        
             
        
        
        
1. a. FeS + 2HCl --> FeCl2 + H2S
    b. This is a double- replacement reaction. (The elements "switch partners".)
2. a.2Na + F2 --> 2NaF
    b. This is a composition/synthesis reaction. (The two reactants are combining or synthesizing to make one product.)
3. a. 2HgO --> 2Hg + O2
    b. This is a decomposition reaction. (The single reactant is breaking down or "decomposing" into multiple reactants.)
4. Hydrogen gas reacts with oxygen gas to create water in a composition/synthesis reaction.
I hope these answers will help you! If you need any explanation, ask and hopefully I can get back to you. ;)