Answer:
A chemical reaction in which an uncombined element replaces an element that is part of a compound is called a simple substitution reaction or simple displacement reaction.
Explanation:
A simple substitution reaction or simple displacement reaction, called single-displacement reaction, is a reaction in which an element of a compound is substituted by another element involved in the reaction. The starting materials are always pure elements and an aqueous compound. And a new pure aqueous compound and a different pure element are generated as products. The general form of a simple substitution reaction is:
AB + C → A +BC
where C and A are pure elements; C replaces A within compound AB to form a new co, placed CB and elementary A.
So, in a Single replacement reaction an uncombined element replaces an element.
<u><em>A chemical reaction in which an uncombined element replaces an element that is part of a compound is called a simple substitution reaction or simple displacement reaction.</em></u>
Answer:
(C) Mass of KCl(s), mass of H20, initial temperature of the water, and final temperature of the solution
Explanation:
molar enthalpy of solution of KCl(s) is heat evolved or absorbed when one mole of KCl is dissolved in water to make pure solution . The heat evolved or absorbed can be calculated by the following relation.
Q = msΔt where m is mass of solution or water , s is specific heat and Δt is change in temperature of water .
So data required is mass of water or solution , initial and final temperature of solution , specific heat of water is known .
Now to know molar heat , we require mass of solute or KCl dissolved to know heat heat absorbed or evolved by dissolution of one mole of solute .
Answer:
1.46g of PbCrO₄ are the theoretical yield
Explanation:
Theoretical yield is defined as the maximum amount of products that could be produced (Assuming a yield of 100%).
The reaction of Lead (II) nitrate with sodium chromate is:
Pb(NO₃)₂(aq) + Na₂CrO₄(aq) → PbCrO₄(s) + 2NaNO₃ (aq)
First, we need to find molar mass of each reactant in order to determine limiting reactant (As the reaction is 1:1, the reactant with the lower number of moles is the limiting reactant). The moles of the limiting reactant = moles of Lead (II) chromate (The precipitate):
<em>Moles Pb(NO₃)₂ -Molar mass: 331.21g/mol-</em>
1.50g * (1mol / 331.21g) = 4.53x10⁻³ moles Pb(NO₃)₂
<em>Moles Na₂CrO₄ -Molar mass: 161.98g/mol-</em>
1.75g * (1mol / 161.98g) = 0.0108 moles
Pb(NO₃)₂ is limiting reactant and moles of PbCrO₄ are 4.53x10⁻³ moles. The mass is:
4.53x10⁻³ moles PbCrO₄ * (323.19g / mol) =
<h3>1.46g of PbCrO₄ are the theoretical yield</h3>
2 A
3 C
4 B
That were the answers to mine
