List of top Questions asked in AP EAPCET

Pure silicon at 300K has equal electron and hole concentration of \( 1.5 \times 10^{16} \) m\(^{-3}\). If the hole concentration increases to \( 3 \times 10^{22} \) m\(^{-3}\), then the electron concentration in the silicon is:

In an \( npn \) transistor circuit, the collector current is \( 10 \) mA. If \( 95\% \) of the electrons emitted reach the collector, then the base current is nearly:

A transmitter of power 10 kW emits radio waves of wavelength 500 m. The number of photons emitted per second by the transmitter is of the order of:

The difference in radii between fourth and third Bohr orbits of \( He^+ \) (in m) is:

If \( \lambda_0 \) and \( \lambda \) are respectively the threshold wavelength and wavelength of incident light, the velocity of photoelectrons ejected from the metal surface is:

The correct order of atomic radii of N, F, Al, Si is:

The correct order of covalent bond character of \( BCl_3, CCl_4, BeCl_2, LiCl \) is:

In which of the following pairs, both molecules possess dipole moment?

At \( T(K) \), the \( P, V \) and \( u_{\text{rms}} \) of 1 mole of an ideal gas were measured. The following graph is obtained. What is its slope (\( m \))? (x-axis = \( PV \); y-axis = \( u_{\text{rms}}^2 \); \( M \) = Molar mass)

Three layers of liquid are flowing over a fixed solid surface as shown below. The correct order of velocity of liquid in these layers is:

A flask contains 98 mg of H₂SO₄. If \( 3.01 \times 10^{20} \) molecules of H₂SO₄ are removed from the flask, the number of moles of H₂SO₄ remaining in the flask is (\( N = 6.02 \times 10^{23} \)):

Identify the correct equation relating \( \Delta H \), \( \Delta U \), and \( \Delta T \) for 1 mole of an ideal gas (R = gas constant):

The number of extensive properties in the following list is: Enthalpy, density, volume, internal energy, temperature.

The equilibrium constant for the dissociation of HI at 773 K is:

The values of \( a \) and \( b \) in the solubility product equation for barium phosphate are:

Hydrated sodium aluminum silicate is called:

Which one of the following statements is NOT correct about the compounds of alkaline earth metals?

Consider the following standard electrode potentials (\(E^\circ\) in volts) in aqueous solution: \includegraphics[]{135.png} Based on this data, which of the following statements is correct?

Which of the allotropic forms of carbon is aromatic in nature?

The enamel present on teeth becomes much harder due to the conversion of hydroxyapatite into fluorapatite. What are \( X \) and \( Y \)?

Number of deactivating groups among: \( -Cl, -SO_3H, -OH, -NHC_2H_5, -COOCH_3, -CH_3 \)

What are \( X \) and \( Y \) respectively in the following reaction sequence?

Identify the incorrect set from the following:

What is the boiling point (in K) of the urea solution from the given graph?

Evaluate the correctness of the given statements.
I. Negative deviation occurs when A-B interactions are stronger than A-A and B-B.
II. Reverse osmosis requires applied pressure greater than osmotic pressure.