The answer to this question would be: BaCl 2
Barium is an alkali metal with 56 atomic number. Barium located in the group 2 of the periodic table because it has 2 valence electrons. Chlorine is a nonmetal that has 1 valence electron. When react, it would need 2 chlorine for each barium as the valence electron of barium is twice the chlorine.
Option 1/A (It is the first one)
Answer:
meter the mean free path of hydrogen atoms in interstellar space.Explanation:
The mean free path equation is given as:

Where"
d = diameter of hydrogen atom in meters
n = number of molecules per unit volume
We are given: d = 100 pm = 



meter the mean free path of hydrogen atoms in interstellar space.
Is it the dry lab/wet lab week 1 or ?
Cells and microorganisms are extremely complex