Answer: -
When bismuth-212 undergoes alpha decay, it becomes ²⁰⁸Tl
Explanation: -
Mass number of ²¹²Bi = 212
Atomic number of ²¹²Bi = 83
When alpha decay occurs the mass number decreases by 4 and the atomic number decreases by 2.
Mass number of daughter = 212 - 4 = 208
Atomic number of daughter = 83 - 2 = 81
It is the atomic number of Thallium Tl.
Thus the daughter nucleide is ²⁰⁸Tl.
NaOH+HCl-> NaCl+H2O
1 mole of NaOH
1 mole of HCl.
To calculate volume of NaOH
CaVa/CbVb= Na/Nb
Where Ca=2M
Cb=1M
Va=200cm³
Vb=xcm³
Substitute into the equation.
2×200/1×Vb=1/1
400/Vb=1/1
Cross multiply
Vb×1=400×1
Vb=400cm³
To calculate the mass of sodium chloride, NaCl from the neutralization rxn.
Mole of NaCl=1
Molar mass of NaCl= 23+35.5=58.5
Mass=xgrammes.
Mass of NaCl=Number of moles × Molar mass.
Substitute
Mass of NaCl= 1×58.5
=58.5g
This is what I could come up with.
Sulfur is a group six element in period 3 with atomic number 16 and an electronic configuration of 2:8:6. Therefore, to attain a stable configuration it requires to gain two electrons forming an ion with a charge of -2. The negative charge is due to the gaining of electrons.