Physical Chemistry - Chemistry Previous Year Questions

Consider a general first order reaction,

$$A(g) \longrightarrow B(g)+C(g)$$

If the initial pressure is 200 mm and after 20 minutes it is 250 mm , then the half-life period of the reaction (in minutes) is ( $\log 2=0.30, \log 3=0.48, \log 4=0.60$ )

4.0 g of a mixture containing $\mathrm{Na}_2 \mathrm{CO}_3$ and $\mathrm{NaHCO}_3$ is heated to 673 K . Loss in mass of the mixture is found to be 0.62 g . The percentage of sodium carbonate in the mixture is

A solid mixture weighing 5 g contains equal number of moles of $\mathrm{Na}_2 \mathrm{CO}_3$ and NaHCO . This solid mixture was dissolved in 1 L of water. What is the volume (in mL ) of 0.1 M HCl required to completely react with this 1 L mixture solution?