The items that are true of early nuclear science are "the first nuclear reactions were done in the 1880s" and "the first nucleus split was uranium-235." <span>The answers are letters A and D. It is impossible that nucleus was lost during the reaction as it will not follow the law of mass conservation.
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10 down: Particle with no charge
Answer: Neutron
Answer: It is important for an equation to be balanced because if it is not then the reactants won't match the products.
Explanation: I don't know if you will understand this but here:
Let's say you're cooking eggs, you're reactants so to speak would be 3 eggs and 1 tablespoon of oil so you put it together using heat and a pan. Your products have to match what you have in the beginning. You cannot have an equation that looks like this
Reactants = 3eggs + 1Tbsp oil ---pan/heat---> 6eggs + 1 cup of oil
You cannot get something from what you don't have. The number of how much of an element you have must be the same of both sides of the equation.
Maximum number of electrons in nth energy level

Now
Max electrons

