Answer:
₈₆²²²Rn → ₈₄Po²¹⁸ + H₂⁴
Explanation:
The given nuclear reaction shows alpha decay.
₈₆²²²Rn → ₈₄Po²¹⁸ + H₂⁴
Properties of alpha radiations:
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
One of the most important characteristic of a metal is its density. As density is the mass of any substance per unit volume. If one can measure the mass of the given shiny metal and its volume then the density of the metal can be determined. The density if matches with the density of the real gold then one can determine the metal is gold or not. The other experiments given will not work in any condition as-
1. Gold doesn't react with water.
2. The hardness of any metals are more than the non-metals and it is not at all an unique property of any metal.
3. All the metals usually reacts with acids or bases with more or less extent. thus it cannot identify the metal is gold or not.
4. The magnetic property is an inherent property of metal. There are several metals which shows magnetic property. Thus gold cannot be identified by this way.
The answer is: The reactants were not heated long enough.
For all chemical reaction some energy is required and that energy is called activation energy (energy that needs to be absorbed for a chemical reaction to start).
Activation energy is the minimum energy colliding particles must have in order to react.
By lowering activation energy, reaction need less heat.
In this example, there is not enough heat.
Answer:
D I'm pretty sure.
Explanation:
I'm taking the quiz right now and D makes the most sense.
