An element’s atomic number is equal to the number of protons in that element’s nucleus. The mass number is the total number of an atom’s protons and neutrons. Protons have a positive charge; electrons have a negative charge; and neutrons are electrically neutral.
Putting it all together, given that the atomic number of lead is 82, the number of protons a lead atom contains is 82. The number of neutrons would be the difference between 207 and 82, or 125 neutrons. Finally, since you have a neutral atom, there must be an equal number of electrons as the number of protons—that is, 82 electrons.
Thus, you’ve got 82 protons, 125 neutrons, and 82 electrons.
Answer:
Mass of carbon = 109.1 g
Explanation:
Given data:
Mass of carbondioxide = 400 g
Mass of carbon = ?
Solution:
Molar mass of carbon = 12 g/mol
Molar mass of CO₂ = 44 g/mol
Mass of carbon in 400g of CO₂:
Mass of carbon = 12 g/mol/44 g/mol × 400 g
Mass of carbon = 109.1 g
The symbol for copper is CU, which means copper cuprum, the Latin word for copper.
Answer:
Many years ago, people living on the Earth, desired to go to the outer space.
Explanation:
When man initiate to go outer space:
Many times ago, people used to think about the world out of Earth, the space and the sky. These thoughts generated the idea of thinking and imagining the space and the moon.
The idea turned into a movie by Georges Méliès, which was inspired by a book written by Jules Verne. The movie gave the idea to Konstantin Tsiolkovsky, a Russian man to develop many ideas which were implemented by Russia and America to build airplanes and rockets that we see launching at present.
A small though became an idea which gave birth to a new invention through which people live their dreams of going in the outer space. Incredible!
