Which of the following reactions of marble with 100cm ?3 of 0.100moldm ?3 HCl is
Which of the following reactions of marble with 100cm?3 of 0.100moldm?3 HCl is fastest?
- A) 5g of marble lump at 50°C
- B) 5g of marble powder at 50°C
- C) 5g of marble powder at 2525°C
- D) 5g of marble lump at 25°C
Correct Answer: B) 5g of marble powder at 50°C
Explanation
Marble is a form of calcium carbonate (CaCO3) and reacts with hydrochloric acid (HCl) to produce calcium chloride (CaCl2), water (H2O), and carbon dioxide (CO2). The reaction can be represented as:
\(CaCO_3 + 2HCl \rightarrow CaCl_2 + H_2O + CO_2\)
There are several factors that can affect the rate of this reaction, including temperature, concentration, and surface area of the reactants. In the given options, we can see that the surface area and temperature are the variables being manipulated.
Option A and Option D involve marble lumps, which have a smaller surface area compared to marble powder. A smaller surface area means less contact between the reactants, leading to a slower reaction rate.
Option B and Option C involve marble powder, which has a larger surface area compared to marble lumps. A larger surface area allows for more contact between the reactants, leading to a faster reaction rate.
Temperature also plays a role in the reaction rate. As temperature increases, the kinetic energy of the molecules increases, leading to more frequent and energetic collisions between reactants. This results in a faster reaction rate. Option B has a higher temperature (50oC) compared to Option C (25oC), and thus will have a faster reaction rate.
Considering both surface area and temperature,Option B: 5g of marble powder at 50oC is the correct answer, as it has the largest surface area and the highest temperature, resulting in the fastest reaction rate.