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The bond energy of H—H and Cl—Cl is $430 \text{ kJ mol}^{-1}$ and $240 \text{ kJ mol}^{-1}$ respectively and $\Delta_f H$ for HCl is $-90 \text{ kJ mol}^{-1}$. The bond enthalpy of HCl is:
If E and G respectively denote energy and gravitational constant, then $\frac{E}{G}$ has the dimensions of
An inductor of inductance $L$, a capacitor of capacitance $C$ and a resistor of resistance $R$ are connected in series to an ac source of potential difference $V$ volts as shown in figure. Potential difference across $L$, $C$ and $R$ are 40 V, 10 V and 40 V, respectively. The amplitude of current flowing through $LCR$ series circuit is $10\sqrt{2}$ A. The impedance of the circuit is
Which of the following refer to correct example(s) of organisms which have evolved due to changes in environment brought about by anthropogenic action? (a) Darwin's Finches of Galapagos islands. (b) Herbicide resistant weeds. (c) Drug resistant eukaryotes. (d) Man-created breeds of domesticated animals like dogs.
A spherical conductor of radius $10 \text{ cm}$ has a charge of $3.2 \times 10^{-7} \text{ C}$ distributed uniformly. What is the magnitude of electric field at a point $15 \text{ cm}$ from the centre of the sphere? ($\frac{1}{4\pi \epsilon_0} = 9 \times 10^9 \text{ Nm}^2/\text{C}^2$)
Column-I gives certain physical terms associated with flow of current through a metallic conductor. Column-II gives some mathematical relations involving electrical quantities. Match Column-I and Column-II with appropriate relations. Column-I: (A) Drift Velocity, (B) Electrical Resistivity, (C) Relaxation Period, (D) Current Density. Column-II: (P) $\frac{m}{ne^2\rho}$, (Q) $nev_d$, (R) $\frac{eE}{m}\tau$, (S) $\frac{E}{J}$
The escape velocity from the Earth's surface is v. The escape velocity from the surface of another planet having a radius, four times that of Earth and same mass density is
The standard enthalpy of vaporisation $\Delta_{vap}H^{\circ}$ for water at $100^{\circ}\text{C}$ is $40.66 \text{ kJ mol}^{-1}$. The internal energy of vaporisation of water at $100^{\circ}\text{C}$ (in $\text{kJ mol}^{-1}$) is: (Assume water vapour to behave like an ideal gas)
A process among the following shows decrease in entropy is :
<p class="p1" style="font-width: normal; font-size: 10px; line-height: normal; font-family: Helvetica; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal; color: rgb(20, 20, 19); white-space: normal;">The partial pressures (in mm Hg) of oxygen (O<span class="s1" style="font-width: normal; font-size: 7px; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">2</span>) and</p><p class="p1" style="font-width: normal; font-size: 10px; line-height: normal; font-family: Helvetica; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal; color: rgb(20, 20, 19); white-space: normal;">carbon dioxide (CO<span class="s1" style="font-width: normal; font-size: 7px; line-height: normal; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal;">2</span>) at alveoli (the site of diffusion)</p><p class="p1" style="font-width: normal; font-size: 10px; line-height: normal; font-family: Helvetica; font-size-adjust: none; font-kerning: auto; font-variant-alternates: normal; font-variant-ligatures: normal; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-position: normal; font-feature-settings: normal; font-optical-sizing: auto; font-variation-settings: normal; color: rgb(20, 20, 19); white-space: normal;">are:</p>
What is the IUPAC name of the organic compound formed in the following chemical reaction? Acetone $\xrightarrow[(ii) H_2O, H^+]{(i) C_2H_5MgBr, dry Ether}$ Product
Identify the basic amino acid from the following.
Match the following with respect to meiosis: (a) Zygotene, (b) Pachytene, (c) Diplotene, (d) Diakinesis. (i) Terminalization, (ii) Chiasmata, (iii) Crossing over, (iv) Synapsis.
The work done when $1 \text{ mole}$ of gas expands reversibly and isothermally from a pressure of $5 \text{ atm}$ to $1 \text{ atm}$ at $300 \text{ K}$ is: [Given: $\log 5 = 0.6989$ and $R = 8.314 \text{ J K}^{-1} \text{ mol}^{-1}$]
Match the following columns and select the correct option. Column I: (a) Eosinophils, (b) Basophils, (c) Neutrophils, (d) Lymphocytes. Column II: (i) Immune response, (ii) Phagocytosis, (iii) Release histaminase, destructive enzymes, (iv) Release granules containing histamine.
A particle moving in a circle of radius $R$ with a uniform speed takes a time $T$ to complete one revolution. If this particle were projected with the same speed at an angle $\theta$ to the horizontal, the maximum height attained by it equals $4R$. The angle of projection, $\theta$, is then given by :
A point object is placed at a distance of 60 cm from a convex lens of focal length 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of
In a Young's double slit experiment, a student observes $8$ fringes in a certain segment of screen when a monochromatic light of $600\text{ nm}$ wavelength is used. If the wavelength of light is changed to $400\text{ nm}$, then the number of fringes he would observe in the same region of the screen is
A cup of coffee cools from $90^{\circ}C$ to $80^{\circ}C$ in $t$ minutes, when the room temperature is $20^{\circ}C$. The time taken by a similar cup of coffee to cool from $80^{\circ}C$ to $60^{\circ}C$ at a room temperature same at $20^{\circ}C$ is
The allele for tallness is dominant over that of dwarfness. This is called: