Answer:
Explanation: It has been given that the temperature of the water decreases when chromium chloride is dissolved in water. Thus fall in the temperature explains the fact that the bond energies of the reactants have more energy rather than the products.
a) Thus the heat of the solution is endothermic in nature as more energy is needed to break the reactant molecules.
b) The combined ionic bond strength of CrCl2 and inter molecular forces between water molecules must be stronger than the attractive forces between the water molecules and chromium and chloride ions as the reaction is endothermic in nature thus more energy would be required to break the bonds between the reactants hence making them more stronger.
Answer:
V = 5 cm³
ρ = 4 g/cm³
Explanation:
Step 1: Calculate the volume (V)
We have a wooden cuboid of dimensions 5 cm × 1 cm × 1 cm. We can calculate its volume using the following expression.
V = 5 cm × 1 cm × 1 cm
V = 5 cm³
Step 2: Calculate the density (ρ)
The density is equal to the mass divided by the volume.
ρ = m / V
ρ = 20 g / 5 cm³
ρ = 4 g/cm³
Answer:- As per the question is asked, 35.0 moles of acetylene gives 70 moles of carbon dioxide but if we solve the problem using the limiting reactant which is oxygen then 67.2 moles of carbon dioxide will form.
Solution:- The balanced equation for the combustion of acetylene is:

From the balanced equation, two moles of acetylene gives four moles of carbon dioxide. Using dimensional analysis we could show the calculations for the formation of carbon dioxide by the combustion of 35.0 moles of acetylene.

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The next part is, how we choose 35.0 moles of acetylene and not 84.0 moles of oxygen.
From balanced equation, there is 2:5 mol ratio between acetylene and oxygen. Let's calculate the moles of oxygen required to react completely with 35.0 moles of acetylene.

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Calculations shows that 87.5 moles of oxygen are required to react completely with 35.0 moles of acetylene. Since only 84.0 moles of oxygen are available, the limiting reactant is oxygen, so 35.0 moles of acetylene will not react completely as it is excess reactant.
So, the theoretical yield should be calculated using 84.0 moles of oxygen as:

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Answer:
The pressure increases to 3.5 atm.
Solution:
According to Gay-Lussac's Law, " At constant volume and mass the pressure of gas is directly proportional to the applied temperature".
For initial and final states of a gas the equation is,
P₁ / T₁ = P₂ / T₂
Solving for P₂,
P₂ = P₁ T₂ / T₁ ----- (1)
Data Given;
P₁ = 3 atm
T₁ = 27 °C + 273 = 300 K
T₂ = 77 °C + 273 = 350 K
Putting values in eq. 1,
P₂ = (3 atm × 350 K) ÷ 300 K
P₂ = 3.5 atm