 # Numerical Problems Based Chemistry Question Paper in pdf

Here are some numerical problems in chemistry for NEET exams:

What is the pH of a solution that contains 0.1 M HCl?

Solution: HCl is a strong acid, which means it completely dissociates in water. So, [H+] = 0.1 M. Using the pH formula, pH = -log[H+], we get:

pH = -log(0.1) = 1

Therefore, the pH of the solution is 1.

Calculate the molarity of a solution that contains 5 grams of NaOH dissolved in 500 mL of water.

Solution: The molar mass of NaOH is 40 g/mol. To calculate the number of moles of NaOH, we need to divide the mass by the molar mass:

Number of moles of NaOH = 5 g / 40 g/mol = 0.125 mol

Now, we need to calculate the molarity of the solution, which is the number of moles of solute per liter of solution. We have 0.125 mol of NaOH in 500 mL (0.5 L) of solution:

Molarity = 0.125 mol / 0.5 L = 0.25 M

Therefore, the molarity of the solution is 0.25 M.

How many grams of CO2 are produced when 2 moles of C3H8 are burned in excess oxygen?

Solution: The balanced chemical equation for the combustion of propane (C3H8) is:

C3H8 + 5O2 3CO2 + 4H2O

According to the equation, 1 mole of C3H8 produces 3 moles of CO2. Therefore, 2 moles of C3H8 will produce:

2 moles C3H8 × (3 moles CO2 / 1 mole C3H8) = 6 moles CO2

To convert moles of CO2 to grams, we need to use the molar mass of CO2, which is 44 g/mol:

Mass of CO2 = 6 moles × 44 g/mol = 264 g

Therefore, 264 grams of CO2 are produced when 2 moles of C3H8 are burned in excess oxygen.