0
Two. Period 1 contains H and He.
Wiki User
∙ 11y ago
Wiki User
∙ 13y ago8
Add your answer:
Earn +20 pts
What is the change in atomic radii for the elements in period 2?
Seventeen
Why does the change for the atomic radii of the elements for period 3 from sodium to argon look similar to period 2?
Because the trend is the same. Atomic radius decreases from left to right across a period.
What is the period and group number for the element with an atomic number of 88?
Radium (atomic no. 88): Group 2 (Alkaline Earth Metals), period 7 of the periodic table of elements.
How many elements in the first period?
Period 1: 2 elements Period 2: 8 elements Period 3: 8 elements Period 4: 18 elements Period 5: 18 elements Period 6: 32 elements Period 7: 25 elements
How do you identify a compound or an element?
Elements are pretty much defined by the number of protons in the nucleus. This number (the atomic number) defines the element. All the different elements have different numbers of protons in their nucleus.
What is the change in atomic radii for the elements in period 2?
Seventeen
What is atomic number of mercury tetra thiocynatecobalt 2?
Only elements have atomic numbers, not compounds.
Why are the elements 94 through 110 in the periodic table whole numbers?
1. All the atomic numbers are whole numbers. 2. If you think to atomic weight of heavy radioactive elements (atomic numbers from 93 to 118) is a rule of IUPAC to indicate in square parenthesis, [], the atomic mass of the most stable or known isotope.
What is the chang ein the atomic radio for the elements in period 2 from lithium to neon?
42
Which element in the 2 period has the greatest atomic radius?
Neon (Ne) in the second period on the periodic table of the elements has the highest atomic number in that period of 10.
Why does the change for the atomic radii of the elements for period 3 from sodium to argon look similar to period 2?
Because the trend is the same. Atomic radius decreases from left to right across a period.
Why does the change for the atomic radii of elements in period 3 from sodium to argon look similar to period 2?
Because the trend is the same. Atomic radius decreases from left to right across a period.
What Element is in group 2 period 2?
Ba, Barium, Atomic #56, is in Group-2 Period-6 of the Periodic Table of the Elements.
What is the period and group number for the element with an atomic number of 88?
Radium (atomic no. 88): Group 2 (Alkaline Earth Metals), period 7 of the periodic table of elements.
How many elements in the first period?
Period 1: 2 elements Period 2: 8 elements Period 3: 8 elements Period 4: 18 elements Period 5: 18 elements Period 6: 32 elements Period 7: 25 elements
What is the atomic number of an atom that has 2 protons and 3 neutrons?
5: The mass number of an isotope is always the sum of the numbers of protons and neutrons in a nucleus of elements of the isotope.
Does elements on the periodic table decrease in atomic size when you move across a period from left to right and when you move down a group?
1. In a period is a trend of decrease from left to right but it is not absolute.2. In a group the atomic radius increase moving down.
