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:
Q = 5555.6J
Explanation:
Mass of glass piece, m = 453g
initial temperature = 25.7°C
temperature to be attained = 40.3°C
⇒change in temperature, Δt = 40.3 - 25.7 = 14.6°C
specific heat of glass, s = 0.840J/g°C
Heat absorbed, Q = msΔt
⇒Q = 453×0.840×14.6 = 5555.592J
⇒<u>Q = 5555.6J</u> (rounded to the nearest tenth)
Every mole is 22.4 L at STP