What is the first 20 elements in science?

Answer 1

1-H,2-He,3-Li,4-Be,5-B,6-C,7-N,8-O,9-F,10-Ne 11-Na,12-Mg,13-Al,14-Si,15-P,16-S,17-Cl,18-Ar,19-K,20-Ca

Answer 2

hydrogen, helium, lithium, beryllium ,boron, carbon, nitrogen ,oxygen , fluorine neon, sodium, magnesium, aluminium, silicon, phosphorous, sulfur, chlorine, argon potassium, calcium,

NOW YOU KNOW YOUR FIRST 20 ELEMENTS WELL DONE

Answer 3

Element/ Atomic Number:

1). Hydrogen H=Symbol

2). Helium He

3). Lithium Li

4). Beryllium Be

5). Boron B

6). Carbon C

7). Nitrogen N

8). Oxygen O

9). Fluorine F

10). Neon Ne

11). Sodium Na

12). Magnesium Mg

13). Aluminium Al

14). Silicon Si

15). Phosphorus P

16). Sulfur S

17). Chlorine Cl

18). Argon Ar

19). Potassium K

20). Calcium Ca

The atomic number is the number of protons in a nucleus which is equal to the number of electrons.

An proton has a positive charge An electron has an negative charge

The number of Electrons cancels out with the number of Protons (that is why all element are neutral).

The mass number is the amount of electrons plus the number of Protons in an

individual Element.

The number of neutrons contained in a nucleus is the mass number minus the atomic number. EG. In Sodium the mass number is 23 minus the atomic number which is equal to 11. Therefor the number of neutrons is 12. (23- 11=12).

In an element there is an electron structure, that is the amount of electrons contained in each shell. The first shell can only 2 electrons, The 2nd can contain the maximum of 8 electrons. Although the 3rd shell can hold 18 electrons, it does not stay that way as over 8 electrons in the 3rd shell, is too powerful. Therefor in an element, you will find there is only a maximum of 8 electrons in it. The cycle continuous of only 8 electrons in the other shells like the third one.

The valence electron is the amount of electrons in the OUTER shell.

Hope this helps,

Hint: Every element has its own state at room temperature and the properties of whether it is an Metal, Metalloid or non-metal.

Answer 4

Hydrogen, helium, lithium beryllium boron, carbon, nitrogen, oxygen, florienne, neon, sodium, magnesium, aluminum, silicon phosphorus sulfur, chlorine, argon, potassium calcium

PS: i might have spelled florienne wrong

Answer 5

hydrogen helium lithium berylium boron carbon nutrogen oxygen florine neon sodium magnesium alminium silicon phosphorus sulpher cholrine argon potasium calcium

(i know 51 straght off)

Answer 6

First 20 elements are:

H,He,Li,Be,B,C,N,O,F,N/E,Na,Mg,Al,Si,P,S,Cl,Ar,K,Ca

Answer 7

Sexx