<u>Given:</u>
Mass of pure iron (Fe) = 3.4 g
<u>To determine:</u>
Mass of HBr needed to dissolve the above iron
<u>Explanation:</u>
Reaction between HBr and Fe is
Fe + 2HBr → FeBr₂ + H₂
Based on the reaction stoichiometry-
1 mole of Fe reacts with 2 moles of HBr
# moles of Fe = mass of Fe/atomic mass of Fe = 3.4/56 g.mol⁻¹ = 0.0607 moles
Therefore # moles of HBr = 2*0.0607 = 0.1214 moles
Molar mass of HBr = 81 g/mole
Mass of HBr = 0.1214 moles * 81 g/mole = 9.83 g
Ans: Mass of HBR required is 9.83 g
<u>Answer:</u> The atomic symbol of the given element is 
<u>Explanation:</u>
The general isotopic representation of an element is given as: 
where,
Z represents the atomic number of the element
A represents the mass number of the element
X represents the symbol of an element
For the given isotope: 130-iodine
Mass number = 130
Atomic number = 53
Hence, the atomic symbol of the given element is 
hey mate here is ur answer
solution
mass{m}=3 gram
=3/1000
volume{v}=16cm
=16/100
density=m/v
=3/1000÷16/100
=3/160
=0.01875kg/m3
Explanation:
a) 3Pb(NO3)2 + Al2(SO4)3 ---> 3PbSO4 + 2Al(NO3)3
Double displacement
b) 2Cl2 + 3O2 ---> 2Cl2O3
Synthesis
c) 2Fe2O3 + 3C ---> 4Fe + 3CO2
single displacement