Answer:
Electrons
Explanation:
Cathode rays carry electronic currents through the tube. Electrons were first discovered as the constituents of cathode rays. J.J. Thomson used the cathode ray tube to determine that atoms had small negatively charged particles inside of them, which he called “electrons.”
 
        
                    
             
        
        
        
Answer:
Answers are explained below
Explanation:
(a)
Oxidation number of iron :
FeO = +2
Fe2O3= +3
Fe3O4 = +2 and +3 since Fe3O4 is the mixture of FeO and Fe2O3.
(b) FeO + CO ----> Fe (s) + CO2
(c) In a pure iron metallic bond is exist between the particles of Fe. But in the form of ore metals forms ionic bond with the non-metals.
Hence the properties vary.
Yes carbon steel has greater strength than that of pure iron but retains the property of iron because no chemical reaction occurs between carbon and iron.
d)
Mixing of carbon in iron is a type of physical change since there is no chemical reactions occur between the carbon and iron. Carbon atoms diffuses in the place between the iron atoms.
(f) One of the property of non-metals are brittleness. It is non ductile .
So when the percentage of carbon increases its atoms also occupying more and more free places.
And increasing the brittleness. So the iron becomes less ductile.
e)
 
        
             
        
        
        
At the first reaction when 2HBr(g) ⇄ H2(g) + Br2(g)
So Kc = [H2] [Br2] / [HBr]^2
7.04X10^-2 = [H2][Br] / [HBr]^2
at the second reaction when 1/2 H2(g) + 1/2 Br2 (g) ⇄ HBr
Its Kc value will = [HBr] / [H2]^1/2*[Br2]^1/2
we will make the first formula of Kc upside down:
1/7.04X10^-2 = [HBr]^2/[H2][Br2]
and by taking the square root: 
∴ √(1/7.04X10^-2)= [HBr] / [H2]^1/2*[Br]^1/2
∴ Kc for the second reaction = √(1/7.04X10^-2) = 3.769 
        
             
        
        
        
MgCO3 + 2LiCl is the product of the above reaction. 
Hope this helps you.
        
                    
             
        
        
        
Answer:
They're called Jovian planets