Chemistry Some Basic Concepts of Chemistry

100g of an ideal gas is kept in a cylinder of 146 L volume at 27°C under 1.5 bar pressure. The molar mass of the gas is _________g mol^-1. (Nearest integer)

(Given : R = 0.083 L bar K^-1 mol^-1)

A box contains 0.90g of liquid water in equilibrium with water vapour at 27°C. The equilibrium vapour pressure of water at 27°C is 32.0 Torr. When the volume of the box is increased, some of the liquid water evaporates to maintain the equilibrium pressure. If all the liquid water evaporates, then the volume of the box must be________ litre. [Nearest Integer]

(Given : R = 0.082 L atm K^-1 mole^-1)

(Ignore the volume of the liquid water and assume water vapours behave as an ideal gas.)

Compound A contains 8.7% Hydrogen, 74% Carbon and 17.3% Nitrogen. The molecular formula of the compound is,

Given : Atomic masses of C,H and N are 12, 1 and 14 amu respectively. The molar mass of the compound A is 162 g mol^-1.

For complete combustion of methanol

$C{H}_{3}OH\left(1\right)+\frac{3}{2}{O}_2\left(g\right)\to C{O}_2\left(g\right)+2H_{2}O\left(I\right)$            

The amount of heat produced as measured by bomb calorimeter is 726 kJmol^-1 at 27°C. The enthalpy of combustion for the reaction is -x kJ mol^-1, where x is_________

(Nearest integer)

(Given : R = 8.3 J K^-1 mol^-1).

Hemoglobin contains 0.34% of iron by mass. The number of Fe atoms in 3.3g of hemoglobin is (Given: Atomic mass of Fe is 56 u, N_A = 6.022 * 10²³ mol^-1.)