To determine the mass of CO₂, the following must be known :
- the molar mass of CaCO₃
- the mole ratio of CaCO₃ to CO₂
- the molar mass of CO₂
<h3>Further explanation</h3>
Reaction
Decomposition of CaCO₃
CaCO₃ ⇒ CaO + CO₂
Given the mass of CaCO₃, so to determine the mass of CO₂ :
1. Find the mol of CaCO₃ from the molar mass of CaCO₃
2. Find the mole ratio of CaCO₃ : CO₂(from equation = 1 : 1)
3. Find the mass of CO₂ from the molar mass of CO₂
The correct answer is Shale
Concentration of a solution can be expressed in terms of molarity and molality
Molarity is the number of moles of solute in a liter of a solution.
Molarity (M) = Moles of solute/Volume(litres) of solution
Molality is the number of moles of solute in one kg of the solution
Molality (m) = Moles of solute/Mass (kg) of solution
Therefore if the volume or the mass of the solution is changed this would affect the concentration.
In addition, volume is a quantity which depends on temperature. However, mass is independent of temperature. Therefore any changes in temperature, can also bring about a change in the molarity of the solution.
<h3>
Answer:</h3>
Gas law : Boyle's law
New pressure: 66.24 atm
<h3>
Explanation:</h3>
Concept tested: Gas laws (Boyle's law)
<u>We are given,</u>
- Initial pressure, P₁ = 2.86 atm
- Initial volume, V₁ = 8472 mL
- New volume, V₂ IS 365.8 mL
We need to determine the new pressure, P₂
- According to Boyle's law , the volume of a fixed mass of a gas and the pressure are inversely proportional at constant temperature.
- That is,
- This means , PV = k (constant)
- Therefore; P₁V₁ = P₂V₂
- Rearranging the formula, we can get the new pressure, P₂
P₂ = P₁V₁ ÷ V₂
= (2.86 atm × 8472 mL) ÷ 365.8 mL
= 66.24 atm
Therefore, the new pressure is 66.24 atm
