Answer:
²³⁰₉₀Th
Explanation:
X → ²²⁶₈₈Ra + ⁴₂He
The given equation shows the alpha emission. When He particle emit the original atom convert into the atom having mass number less than 4 and atomic number less than 2 as compared to parent atom the starting atom. It means the parent atom is ²³⁰₉₀Th.
Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4 and atomic number less than 2 as compared to parent atom the starting atom.
Alpha radiations can travel in a short distance.
These radiations can not penetrate into the skin or clothes.
These radiations can be harmful for the human if these are inhaled.
These radiations can be stopped by a piece of paper.
₉₂U²³⁸ → ₉₀Th²³⁴ + ₂He⁴ + energy
Answer:
The answer to your question is 1) 0.037 M 2) 0.32 M 3) 0.096 M
Explanation:
a) 125 ml of 0.251 M HCl
-Calculate the moles of HCl
Molarity = moles/volume
-Solve for moles
moles = Molarity x volume
-Substitution
moles = 0.251 x 0.125
= 0.0314
-Calculate the new molarity
Molarity = 0.0314/ (0.125 + 0.250)
-Simplification
Molarity = 0.014/0.375
-Result
Molarity = 0.037 M
2.-
445 ml of 0.499 M of H₂SO₄
-Calculate the number of moles
moles = 0.499 x 0.445
moles = 0.222
-Calculate the new molarity
Molarity = 0.222/(0.445 + 0.25)
Molarity = 0.222/0.695
Molarity = 0.32
3)
5.25 l of HCO₃ 0.101 M
Calculate the number of moles
moles = 0.101 x 5.25
moles = 0.53
-Calculate the Molarity
Molarity = 0.53 / (0.25 + 5.25)
Molarity = 0.53 / 5.5
Molarity = 0.096
Answer:
О
because it has the fewest number of electrons
N(Na)=0.255 mol
M(Na)=22.990 g/mol
m(Na)=n(Na)M(Na)
m(Na)=0.255*22.990=5.862 g
2 H₂ + O₂ = 2 H₂O
Answer B only synthesis.
hope this helps!