Sodium. 11
Carbon. 12
Hydrogen 1
Oxygen 2
Fluuorine. 14
Boron. 5
Lithium. 6
Helium 3
Phosphorus 15
Sulfur 6
The correct answer is option 1. Be, Mg, and Ca is the correct order arranged in increasing atomic radius. This is predicted based on the periodic table. The atomic sizes increases as one moves downwards in the periodic table.
Your answer is C
amino acids are created by a bond of two carbon atoms and each carbon is part of a different group, one negative and one positive. when the chemical reactions occurs, it creates the several diff amino acids
Answer : The molarity of calcium ion on the original solution is, 0.131 M
Explanation :
The balanced chemical reaction is:

When calcium nitrate react with potassium carbonate to give calcium carbonate as a precipitate and potassium nitrate.
First we have to calculate the moles of 

Given:
Mass of
= 0.524 g
Molar mass of
= 100 g/mol

Now we have to calculate the concentration of 

Now we have to calculate the concentration of calcium ion.
As, calcium carbonate dissociate to give calcium ion and carbonate ion.

So,
Concentration of calcium ion = Concentration of
= 0.131 M
Thus, the concentration or molarity of calcium ion on the original solution is, 0.131 M
Water decomposes when electrolyzed to produce hydrogen and oxygen gas. If 2.5 grams of water were decomposed 1.04 grams of oxygen will be formed.
BCA table:
2
O ⇒
+ 
B 0.13 0 + 0
C -0.13 0.065 + 0.065
A 0 0.065
Explanation:
Balanced equation for water decomposition into hydrogen and oxygen gases
2
O ⇒
+ 
B 0.13 0 + 0
C -0.13 0.065 + 0.065
A 0 0.065
Number of moles of water = 
mass = 2.5 grams
atomic mass= 18 grams
number of moles can be known by putting the values in the formula,
n = 
= 0.13 moles
2 moles of water gives one mole of oxygen on decomposition
so, 0.13 moles of water will give x moles of oxygen on decompsition
= 
x = 0.065 moles of oxygen will be formed.
moles to gram will be calculated as
mass =number of moles x atomic mass
= 0.065 x 16
= 1.04 grams of oxygen.