Answer:
40 electrons
Explanation:
The element of zirconium (Zr) has an atomic number of 40, which means it has 40 protons and 40 electrons. It also has a molar mass of 91.224 g/mol.
The building block of matter are atoms
Answer:
Explanation:
In Pre-AP Chemistry, the development of models to explain their macroscopic observations is a primary means through which students develop an understanding of the molecular world.
You will be forced to think and apply concepts to new situations, and even derive your own theories from application. This is excellent preparation for the higher levels of thinking required in college.
Chemistry, the science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during these processes.
Answer:
1. an object that has been intentionally placed into orbit. they are called Artificial Satalites.Satanists.
2. a huge collection of gas ,dust and billions of stars and their solar systems held together by gravity.
3. a large object such as Jupiter or Earth that orbits a star. planets are smaller than stars and they do not produce light.
4. July 16, 1969
