Answer:
Alpha particle or helium nuclei.
Explanation:
Alpha particle:
Alpha particle is 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.
Properties of alpha radiation:
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: 
formula units
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number 
of particles.
To calculate the moles, we use the equation:
1 mole of 
contains of formula units
Thus 0.203 mole of contains =
of formula units
The molarity of the solution will be 4.97 M.
<h3>What is molarity?</h3>
It is the number of moles of solutes per 1 liter of solvent or solution.
Mole of 34.1 g NaCl = 34.1/58.44 = 0.5835 mol
117.3 mL = 117.3/1000 = 0.1173 L
Molarity of the solution = 0.5835/0.1173 = 4.97 M
More on molarity can be found here: brainly.com/question/2817451
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Answer:
D
Explanation:
Universe consits of galaxies, galaxies consit of solar systems, and solar systems consist of planets
