Answer:

Explanation:
<h2><u>Displacement reaction:</u></h2>
- A reaction in which an element displaces or replaces another element of a compound is called a displacement reaction.
<h3><u>Types:</u></h3>
There are 2 types:
<h3><u>1. Single displacement reaction:</u></h3>
- If one element displaces 1 other element of a compound, it is called single displacement reaction.
- <u>Example</u>:

- Here, 1 element (Fe) displaces 1 other element (Cu) of a compound.
<h3><u>2. Double displacement reaction:</u></h3>
- If two elements in two compounds displace one another, it is called double displacement reaction.
- <u>Example:</u>

- Here, Copper and sodium both displace each other.
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Answer:
electrons located outside the nucleus
Explanation:
electrons are said to be located outside the nucleus of an atom and are in orbit around the nucleus.
according to Bohr in 1913.
The answer is Strontium(Sr). The reactive increase from right to left. And this element has two valence electrons. So Rb is not correct. Then the very reactive metal is Sr.
<em>m Na₂CO₃: 23g×2 + 12g + 16g×3 = 106 g/mol</em>
------------------------------
1 mol ------- 106g
X ------------ 10,6g
X = 10,6/106
<u>X = 0,1 mol Na₂CO₃</u>
Hydroxide is the full name of the compound.
Hope this Helped!
;D
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