Description : What did the scientist say when he discovered 2 atoms of helium? -Riddles
Last Answer : He he!
Description : The scientist who proved that the ele- ments are made up of atoms?
Last Answer : John Dalton
Description : If the structure is more complex in order to simplify the model, we need to subdividethe structure into substructures. These substructures are termed as . a.elements b.modules c.links d.models
Last Answer : b.modules
Description : What types of models are created during software requirements analysis? (A) Functional and behavioral (B) Algorithmic and data structure (C) Architectural and structural (D) Usability and reliability
Last Answer : (A) Functional and behavioral
Description : Using X-ray crystallography, this woman scientist determined the structures of large biochemical molecules, including penicillin in 1949 and vitamin B12 in 1956. In 1969 she determined the three ... X-ray techniques of the structures of important biochemical substances." Name this woman scientist.
Last Answer : ANSWER: (DOROTHY) CROWFOOT HODGKIN
Description : Write the name and structure of a saturated compound in which the carbon atoms are shaped in a ring. Also write the number of bonds present in that compound? -SST 10th
Last Answer : It’s cyclo alkane, it can be any cyclo alkane like cyclo pentane or cyclo hexane.
Description : Find the structure of the following atoms: (i) `._(8)^(16)O" "` (ii) `._(17)^(35)Cl" "` (iii) `._(13)^(27)Al`.
Last Answer : Find the structure of the following atoms: (i) `._(8)^(16)O" "` (ii) `._(17)^(35)Cl" "` (iii) `._(13)^(27)Al`.
Description : How many bonds occur between the carbon and nitrogen atoms when drawing the Lewis dot structure for hydrogen cyanide?
Last Answer : Need answer
Description : Prostaglandins have a common structure based on prostanoic acid which contains carbon atoms: (A) 12 (B) 16 (C) 18 (D) 20
Last Answer : Answer : D
Description : Which of the following is not characteristic of resonance? (a) The canonical structures have the constituent atoms in the same relative positions (b) They have nearly the same energy (c) ... of unpaired electrons (d) The actual structure can be represented on paper using the conventional symbols
Last Answer : Ans:(d)
Description : Diamond does not conduct electricity, because - (1) It's structure is very compact (2) It is of crystalline nature (3) There are only carbon atoms present in it (4) No free electrons are present in it
Last Answer : (4) No free electrons are present in it Explanation: Diamond has a giant molecular structure. Each carbon atom is covalently bonded to four other car-bon atoms. There are no ... conduct electricity. Except for most blue diamonds, which are semiconductors, diamonds are good electrical insulators.
Description : Diamond is harder than graphite because of – (1) difference in layers of atoms (2) tetrahedral structure of diamond (3) difference of crystalline structures (4) None of these
Last Answer : (1) difference in layers of atoms Explanation: Diamond is harder than graphite because diamond has a more complex structure. Diamond's structure is like many pentagons connected together, each pentagon ... together in some way. Graphite's structure is very loose, with its bonds forming layers.
Description : Neoprene is rendered non-inflammable, because of (A) Its cross-linked structure (B) Its linear chain structure (C) The presence of chlorine atoms in its monomer (D) The absence of chlorine atoms in its monomer
Last Answer : (C) The presence of chlorine atoms in its monomer
Description : Atoms of U-238 and U-235 differ in structure by three (A) Electrons and three protons (B) Protons (C) Neutrons (D) Electrons
Last Answer : (C) Neutrons
Description : Benzene undergoes substitution reaction more easily than addition reaction because (a) it has a cyclic structure (b) it has three double bonds (c) it has six hydrogen atoms (d) there is delocalization of electrons
Last Answer : there is delocalization of electrons
Description : What is the hybridization of the carbon atoms numbered 1 and 2 respectively in the following structure? (a) sp3, sp2 (b) sp2, sp2 (c) sp, sp (d) sp2, sp
Last Answer : sp2, sp
Description : Out of the following, the lowest packing of atoms exists in __________ crystal lattice structure. (A) Hexagonal close, packed (hcp) (B) Face centred cubic (fcc) (C) Body centred cubic (bcc) (D) Simple cubic
Last Answer : (D) Simple cubic
Description : In an amorphous material, atoms defy any definite atomic structure and exist in random pattern just like in liquid. Which of the following is an amorphous material? (A) Tin (B) Lead (C) Zinc (D) Glass
Last Answer : Option D
Description : How many neighboring atoms are in contact with each a in a hexagonal close-packed structure?
Last Answer : ANSWER: 12
Description : How many neighboring atoms are in contact with eac atom in a monatomic body-centered cubic structure. w) 4 x) 6 y) 8 z) 12
Last Answer : ANSWER: Y -- 8
Description : Solids may be considered to be either crystalline noncrystalline. The basic difference between them is that a crystal, in contrast to a noncrystal: w) has a sharp melting point x) has an irregular array of atoms y) exhibits double refraction z) has a completely regular atomic or molecular structure
Last Answer : ANSWER: Z -- HAS A COMPLETELY REGULAR ATOMIC OR MOLECULAR STRUCTURE
Description : Diamond does not conduct electricity, because (1) It’s structure is very compact (2) It is of crystalline nature (3) There are only carbon atoms present in it (4) No free electrons are present in it
Last Answer : No free electrons are present in it
Description : Diamond is harder than graphite because of : (1) difference in layers of atoms (2) tetrahedral structure of diamond (3) difference of crystalline structures (4) None of these
Last Answer : difference in layers of atoms
Last Answer : The number of atoms per unit cell in B.C.C. structure is 2.