Choose the correct answer :
1. Production of iron in blast furnace follows the following equation
Fe3O4(s)+4CO(g)→3Fe(I)+4CO22(g)
when 4.640 kg of Fe3O4 and 2.520 kg of CO are allowed to react then the amount of iron (in g) produced is
[Given : Molar Atomic mass (g mol–1) : Fe = 56
Molar Atomic mass (g mol–1) : O = 16
Molar Atomic mass (g mol–1) : C = 12]

The correct option is(C): 3360

Considering Bohr’s atomic model for hydrogen atom :
(A) the energy of H atom in ground state is same as energy of He+ ion in its first excited state. 
(B) the energy of H atom in ground state is same as that for Li++ ion in its second excited state. 
(C) the energy of H atom in its ground state is same as that of He+ ion for its ground state. 
(D) the energy of He+ ion in its first excited state is same as that for Li++ ion in its ground state.
Let $f: [0, \infty) \to \mathbb{R}$ be a differentiable function such that $f(x) = 1 - 2x + \int_0^x e^{x-t} f(t) \, dt$ for all $x \in [0, \infty)$. Then the area of the region bounded by $y = f(x)$ and the coordinate axes is
Quantitative analysis of an organic compound (X) shows the following percentage composition. 
C: 14.5% 
Cl: 64.46% 
H: 1.8% 
Empirical formula mass of the compound (X) is:
If $\lim_{x \to 1} \frac{(x-1)(6+\lambda \cos(x-1)) + \mu \sin(1-x)}{(x-1)^3} = -1$, where $\lambda, \mu \in \mathbb{R}$, then $\lambda + \mu$ is equal to
The atomic structure of an element refers to the constitution of its nucleus and the arrangement of the electrons around it. Primarily, the atomic structure of matter is made up of protons, electrons and neutrons.
Dalton proposed that every matter is composed of atoms that are indivisible and indestructible.
The following are the postulates of his theory:
Several atomic structures of an element can exist, which differ in the total number of nucleons.These variants of elements having a different nucleon number (also known as the mass number) are called isotopes of the element. Therefore, the isotopes of an element have the same number of protons but differ in the number of neutrons. For example, there exist three known naturally occurring isotopes of hydrogen, namely, protium, deuterium, and tritium.