Missing question:
Chemical reaction: H₂ <span>+ 2ICl → 2HCl + I</span>₂.
t₁ = 5 s.
t₂ = 15 s.
c₁ = 1,11 M = 1,11 mol/L.
c₂ = 1,83 mol/L.
rate of formation = Δc ÷ Δt.
rate of formation = (c₂ - c₁) ÷ (t₂ - t₁).
rate of formation = (1,83 mol/L - 1,11 mol/L) ÷ (15 s - 5 s).
rate of formation = 0,72 mol/L ÷ 10 s.
rate of formation = 0,072 mol/L·s.
Formation reaction is the formation of 1 mole of product from the constituents of the reactant molecules. The mass of oxygen that must react is 182 gm.
<h3>What is mass and molar mass?</h3>
Mass of the substance is the weight while the molar mass of the substance is the addition of the atomic mass of the individual mass of the constituent atoms of the compound or the molecule.
The chemical reaction can be shown as:
From the reaction, it can be said that 3 moles of oxygen are required to produce 2 moles of aluminium oxide, so x moles of oxygen will be required to produce 3.80 moles of aluminium oxide.
Solving for x:
If 1 mol of oxygen is 32 gm then 5.7 moles of oxygen will be 182.4 gm.
Therefore, option D. 182 gm is the mass of oxygen required.
Learn more about moles and molar mass here:
brainly.com/question/893495
Answer:
ΔH°r = -1562 kJ
Explanation:
Let's consider the following combustion.
C₂H₆(g) + 7/2 O₂(g) ⇒ 2 CO₂(g) + 3 H₂O(l)
We can calculate the standard heat of reaction (ΔH°r) using the following expression:
ΔH°r = ∑np × ΔH°f(p) - ∑nr × ΔH°f(r)
where,
ni are the moles of reactants and products
ΔH°f(i) are the standard heats of formation of reactants and products
The standard heat of formation of simple substances in their most stable state is zero. That means that ΔH°f(O₂(g)) = 0
ΔH°r = ∑np × ΔH°f(p) - ∑nr × ΔH°f(r)
ΔH°r = [2 mol × ΔH°f(CO₂) + 3 mol × ΔH°f(H₂O)] - [1 mol × ΔH°f(C₂H₆) + 7/2 mol × ΔH°f(O₂)]
ΔH°r = [2 mol × (-394.0 kJ/mol) + 3 mol × (-286.0 kJ/mol)] - [1 mol × (-84.00 kJ/mol) + 7/2 mol × 0]
ΔH°r = -1562 kJ
Answer : The correct option is (C) : Dew forms on grass when water vapor forms when molecules cool and join together.
Explanation :
Air contains a small amount of water vapors. When the temperature of an object is lowered than the ambient temperature, the vapors get condensed and small water droplets are formed on the object.
During night time, when the temperature is lowered, the blades of grass become cool. As a result, the vapor molecules slow down and eventually come close to each other. They join together to form liquid water which gets deposited on the blades in the form of dew drops.
The only option that explains this process is option C.
