Answer:
4.375 milligram
Explanation:
Applying,
A = A'(2ᵃ/ⁿ)............. Equation 1
Where A = original amount of actinium-228, A' = amount of actinium-228 left after decay, a = Total time, n = half life
make A' the subject of the equation
A' = A/(2ᵃ/ⁿ)........... Equation 2
From the question,
Given: A = 70 milligram, a = 24.52 hours, n = 6.13 hours
Substitute these values into equation 2
A' = 70/(2²⁴°⁵²/⁶°¹³)
A' = 70/(2⁴)
A' = 70/16
A' = 4.375 milligram
Answer:
I have the same thing it's hard
Answer:
The answer to your question is below
Explanation:
I just write the formulas of the reactants and products and balanced the reactions.
a)
3H₂(g) + N₂(g) ⇒ 2NH₃
b)
2K + 2H₂O ⇒ 2KOH + H₂ (g)
c)
2Al(s) + Fe₂O₃ ⇒ Al₂O₃ + 2Fe
d)
Fe₂O₃ + 2Al ⇒ Al₂O₃ + 2Fe
e)
Ba(OH)₂ + 2HBr ⇒ BaBr₂ + 2H₂O
f)
CaCO₃ + Δ ⇒ CaO + CO₂
Answer:
For mole conversion always remember 1 mole of compound = molar mass of compound.
Ex. 2 moles H20 to grams
2mol H2O x 18 g / 1mol H20
For molecules use Avogadro's number like moles multiplied to 6.022x10²³ answer will be in molecules.
Explanation:
Sound, light, kinetic, heat energy
