Im pretty Sure its B Tuesday And Wensday
Answer:
A: element B
B: element A
C: element B
D: element A
Explanation:
decrease in size leads increase in electronegativity because the smaller the size, the closer the shell is to the nucleus. Also, atomic radius decreases to the right and up on the periodic table. Atomic radius increases to the left and down a period. I hope this helps!
When sodium carbonate is dissolved in water, the equation is
.
When carbon dioxide is placed in water, aqueous carbon dioxide is formed: 
<h3>Dissolution of compounds in water</h3>
Some compounds are water-soluble, some are just partially soluble, while others are insoluble in water. Some soluble or partially soluble substances dissociate in water into their component ions. These substances are said to be ionic.
Sodium carbonate, like every other sodium salt, is soluble in water. It dissolves in water to form an aqueous solution of sodium carbonate.
While in solution, sodium carbonate dissociates into its component ions according to the following equation:

Carbon dioxide, on the other hand, does not dissociate in water. Instead, it dissolves in water where most of it remains as aqueous carbon dioxide in equilibrium with a small amount of hydronium ion and hydrogen carbonate ion.
Since the hydronium and hydrogen carbonate ions formed are so minute, the equation of the reaction can be written as: 
More on the dissolution of substances can be found here: brainly.com/question/28580758
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17) 8.4 / 20 x 100
18) 20 . 0.5150
19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
Answer:
6
Explanation:
The coordination number of a particular crystal structure arrangement is defined as the number of nearest neighbor atoms or ions surrounding an atom or ion.
We must note that in salts of the type MX, the coordination number of each ion must be equal. The structure of LiCl is built by placing each unit cell next to another such that ions residing in the corner, edge or face sites are shared between adjacent unit cells. The LiCl is in FCC arrangement.
Hence in LiCl, each Li+ ion is surrounded by 6 chloride ions.