Question

Define the following terms
1 atom
2 isotope
3 atomic number
4 atomic mass number
5 moderator in nuclear reactor ​

Answer 1

Answer:

(1) Atom: The smallest part into which an element can be divided.

(2) Isotope: Species having same atomic number but different mass number.

(3) Atomic number: Number of electrons present in an atom which is equal to number of protons in a neutral atom.

(4) Atomic mass number: Sum of the number of protons and neutrons i.e, nucleons present in an atom.

(5) Moderator in nuclear reactor: A material that slows the speed of neutrons.

Explanation:

its help full

mark me. brainlist

Answer 2

$\large \sf \: Answer:- \:$

• An atom is the smallest unit of ordinary matter that forms a chemical element.

• Isotopes are members of a family of an element that all have the same number of protons but different numbers of neutrons.

• The atomic number is the number of protons in the nucleus of an atom.

• Together, the number of protons and the number of neutrons determine an element's mass number: mass number = protons + neutrons. 

• The moderator of a nuclear reactor is a substance that slows neutrons down. When fast neutrons strike the hydrogen atoms in H2O, they slow down a lot (like a billiard ball striking another). There are other good moderators like graphite, beryllium, and more.