I think it’s The second option sorry if I’m wrong
Answer: b} The exact time when an individual atom will decay can be accurately predicted.
c} After each half-life, the amount of radioactive material is reduced by half.
Explanation:
All radioactive decay follows first order kinetics.
Rate law expression for first order kinetics is given by:
where,
k = rate constant
t = time taken for decay process
a = initial amount of the reactant
a - x = amount left after decay process
Expression for calculating half life, which is the time taken by the half of the reactants to decompose is:

The initial mass of sodium hydroxide is 3.3 g (answer C)
<u><em>calculation</em></u>
Step 1 : find the moles of iron (ii) hydroxide ( Fe(OH)₂
moles = mass÷ molar mass
from periodic table the molar mass of Fe(OH)₂ = 56 + [16 +1]2 = 90 g/mol
moles is therefore = 3.70 g÷ 90 g/mol = 0.041 moles
Step 2: use the mole ratio to calculate the moles of sodium hydroxide (NaOH)
from given equation NaOH : Fe(OH)₂ is 2 :1
therefore the moles of NaOH = 0.041 x 2 = 0.082 moles
Step 3: find mass of NaOH
mass = moles x molar mass
from the periodic table the molar mass of NaOH = 23 +16 +1 = 40 g/mol
mass = 0.082 moles x 40 g/mol = 3.3 g ( answer C)
Covalent bonds formed when two atoms share an electron, as opposed to an Ionic bond where one atom takes an electron(or two) from another atom.
Explanation:
hexaaqua iron (III) trinitrate