The mass number of a nucleus is (a) Always less than its atomic number (b) Always more than its atomic number (c) Sometimes more than and sometimes equal to its atomic number (d) None of the above2 23167
The maximum KE of the photoelectron emitted from a surface is dependent on (a) The intensity of incident radiation (b) The potential of the collector electrode (c) The frequency of incident radiation (d) The angle of incidence of radiation of the surface1 2050
Which of the following is not an essential condition for interference (a) The two interfering waves must be propagated in almost the same direction or the two interfering waves must intersect at a very small angle (b) The waves must have the same time period and wavelength (c) Amplitude of the two waves should be the same (d) The interfering beams of light must originate from the same source.1 3681
When X-Ray photons collide with electrons (a) They slow down (b) Their mass increases (c) Their wave length increases (d) Their energy decreases.1 4717
An electron emits energy (a) Because its in orbit (b) When it jumps from one energy level to another (c) Electrons are attracted towards the nucleus (d) The electrostatic force is insufficient to hold the electrons in orbits.1 1656
In a balanced chemical equation (a) Atoms are conserved (b) Molecules are conserved (c) Moles are conserved (d) Reactant and product molecules are preserved.1 18644
How many grams of NaOH will react with 0.2 equivalent of HCl? (a) 0.59 (b) 0.285 (c) 1.18 (d) none of these.2 3776
Which of the following is least acidic (a) Ortho-cresol (b) Para-cresol (c) Phenol (d) Meta-cresol.1 2556
In Reimer-Tiemann?s reaction, the reaction intermediate is (a) Carbene (b) Dichloro carbene (c) Carbonion (d) Carbonium ion.1 8084
Which of the following is most acidic? (a) C2H5OH (b) CH3CHOHCH3 (c) Ethanol (d) CH3OH.1 3625
A catalyst (a)always slows down the reaction (b)always starts a rection that would not have ocurred at all otherwise (c)causes changes in the rate of the reaction (d)changes the quantities of the products formed.1 1689
The rate of the first order reaction depends on the (a) Concentration of the reactant (b) Concentration of the product (c) Time (d) Temperature.1 1817
Integrate 3x + 5 / (x3-x2-x+1)?864
How to identify common acc.numbers from among a set of files ?
How to find a sequence of dna molecule?
How to caculate coordinates of each atoms on 3 D HP model?
What are the main differences between parsimony,distance and likelihood-based algorithms?
What is the product of the irrational roots of the equation (2x-1)(2x-3)(2x-5)(2x-7)=9?
What is a homologue?
What is the idea behind ?weighting? sequences in the package CLUSTAL W for multiple alignment? How are these weights calculated?
Suppose you used the NCBI Blast server to look for a match to a fruit-fly gene. Suppose further that the best alignment contained this section of an alignment: Hit from database: XXXXXXXXXXXXXXNFSTSQ User sequence: SLEAEAAPASISPSNFSSSQ What do the Xs signify?
An electron is injected into a region of uniform magnetic flux density with the components of velocity parallel to and normal to the flux. What is the path of the electron?
What are the current challenges in the Pharmaceutical and biotechnology sectors?
What is a DNA array?
How to find flanking region ?
Define perl and clustalW problem?
what is a qi number?
what is an active ? (UML)