I think it is 11% I read it on a article on msn.
D) life on earth was seeded by extraterrestrial aliens
Answer:
A- beryllium
B- calcium
C- magnesium
Explanation
NOTE: all element in group 2 have 2 balance electrons
First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20
C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).
A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.
Answer:
Explanation:
Which is more reactive hydrogen or oxygen?
Hydrogen is not particularly reactive. For example, just mixing hydrogen and oxygen gas will not cause a reaction at room temperature, but many metal elements oxidize at least on the surface in air. ... It is combustible because oxygen wants electrons and takes them from hydrogen to form water.
In order to float the demsoty of the floating obkect must be lower then the liquid it is in. the only one that works for is Citric acid