Answer:
DE2
Explanation: for every one D+2 you need two E-1 because +2=-2
Answer:
Explanation:
Atom X,
Neutron num = 4, Mass num = 7
Therefore, proton number = Mass num - Neutron num
= 7 - 4
= 3
Atom Y,
Neutron num = 5, Mass num = 9
Therefore, proton number = Mass num - Neutron num
= 9 - 5
= 4
1) False. Atom X belongs to group 3 while atom Y belongs to group 4
2) False. Atom X is in a column on the left of Atom Y
3) True. Atom X and atom Y belong to the same period two on the periodic table
4) Fasle. Atom X and Y are not isotopes because they do not have the same atomic number.
Isotopy is a phenomenon whereby atom of same element have same atomic number but different mass number
Answer:
Na(OH)²
Explanation:
We look for the charges in the periodic table
Marie Curie discovered polonium and radium. Hope this helps:))) Please, mark Brainliest!
it only happensonce every 7 years
