Answer: a) 
b) 
c) 
d) 
Explanation:
General representation of an element is given as:_Z^A\textrm{X}
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
In an atom, when neutrons or protons are lost or gains, it directly affects the mass number of an atom.
Atomic number is defined as the number of protons or number of electrons that are present in an atom.
It is characteristic of a particular element.
Atomic number = Number of electrons = Number of proton
a) Z 74, A 186:
b) Z 80, A 201:
c) Z 34, A 76:
d) Z 94, A 239.:
1. Nickel (II) Bromide
2. Iron (II) Oxide
3. Iron (III) Oxide
4. Tin (IV) Chloride
5. Lead (IV) tetrachloride
6. Tin (II) Bromide
7. Chromium (III) Phosphide
8. Iron (II) Fluoride
9. Gold (III) Chloride
I hope this helps. I'm more than 100% sure that all the answers except for number 7 are correct. I knew all of them off the top of my head except for this one. I hope the other answer has the correct answer for that one. Good luck and have a great day.
An atom is the smallest unit of ordinary matter that forms a chemical element.
oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.
Answer:
Curd, lemon juice, orange juice and vinegar taste sour. These substances taste sour because they contain acids. The chemical nature of such substances is acidic. The word acid comes from the Latin word acere which means sour.
