Answer:
Explanation: Atoms are the building blocks of all matter. They consist of three sub-atomic particles: protons, neutrons and electrons. Protons and neutrons are found in the nucleus of an atom. Electrons are found in energy levels around the nucleus as shown in the diagram representing a carbon atom with 6 protons, 6 neutrons and 6 electrons.
Sub-atomic particles
Particle Whereabouts in atom Relative mass Charge
Proton Nucleus 1 +1
Neutron Nucleus 1 0
Electron Outside the nucleus 1/1840 -1
Diagram of carbon atom - nucleus with electrons orbiting
Diagram of carbon atom - nucleus with electrons orbiting
In chemistry we are particularly interested in electrons. As you will see later, this is because chemical reactions involve the rearrangement of electrons. Nuclei of atoms (protons and neutrons) usually remain unchanged (except in radioactive decay).
Electrons are arranged in atoms according to their energies. This is called the electronic structure or electronic configuration of the atom. A crude but still useful model says the electrons can be in different energy levels. Electrons in a particular energy level all have the same energy as one another. The lowest energy level can accommodate up to 2 electrons. The second level can accommodate up to 8 electrons. The third level can accommodate up to 18 electrons. The diagram shows the situation for a sulfur atom.
Electronic configuration of sulfur including energy level diagram
Answer: A solid has a defined shape and volume. A common example is ice.
A liquid has a defined volume, but can change state. An example is liquid water.
A gas has neither a defined shape nor volume. Water vapor is an example of a gas
Answer:
Mass = 1785.6 g
Explanation:
Given data:
Moles of lead oxide = 8 mol
Mass in grams = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Mass = number of moles × molar mass
Molar mass of PbO = 223.2 g/mol
Now we will put the values.
Mass = 8 mol × 223.2 g/mol
Mass = 1785.6 g
Thus 8 moles of lead oxide have 1785.6 grams.
For question two, you figure out the amount of sodium atoms on the left and right side and the amount of oxygen atoms on the left and right side
So for two it would be 4, 1, 2
For question four, you figure out the amount of atoms on each side
So for four it would be 1, 2, 1, 2
One mole contains 6.02×10²³
If x mole contains 3.131×10²⁴
x = 3.131×10²⁴
-------------
6.02×10²³
x = 0.52×10²⁴¯²³
x = 0.52×10¹
x = 5.2moles....
Hope this helped...?
