The periodic table is grouped by the properties of each element. They are also arranged in the order of their atomic mass. Different rows of elements are called periods. If elements lie in the same column, they are in the same group. It is helpful to us today because it helps us gain new information on the properties and the world around us. We would not have a true understanding of Chemistry if it were not for the period table.
Answer:
An atom cannot be subdivided into smaller particles. (Option A).
Explanation:
According to Dalton's atomic theory: All matter is composed of tiny particles called as atoms. Some postulates of this theory are given below:
1) An atom cannot be subdivided into smaller particles it means they are indivisible.
2) Different element atoms have different masses, and chemical properties.
3) All atoms which are present in an element are identical in all respects such as mass, chemical properties, etc.
4) Atom cannot create or destroyed in a closed system.
5) The types of atoms, and relative number are constant in a given compound.
Answer:
0.12693 mg/L
Explanation:
First we <u>calculate the concentration of compound X in the standard prior to dilution</u>:
- 10.751 mg / 100 mL = 0.10751 mg/mL
Then we <u>calculate the concentration of compound X in the standard after dilution</u>:
- 0.10751 mg/mL * 5 mL / 25 mL = 0.021502 mg/L
Now we calculate the<u> concentration of compound X in the sample</u>, using the <em>known concentration of standard and the given areas</em>:
- 2582 * 0.021502 mg/L ÷ 4374 = 0.012693 mg/L
Finally we <u>calculate the concentration of X in the sample prior to dilution</u>:
- 0.012693 mg/L * 50 mL / 5 mL = 0.12693 mg/L
Atomic number of neon: 10
atomic mass of neon: 20.18