Number of stomata present per `cm^(2)` of a common leaf is aboout
A. Less then 100
B. More than 100,000
C. 1 million
D. 10000
1 Answers
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When a tuning fork A and B are sounded together,the number of beats heard are 4 per second.When tuning fork A is field,the number of beats heard per s
Correct Answer - D `n_(A) = 300 Hz` `n_(B) = 384 +- 3 = 387 or 381` After filling frequency increases before filling frequency decreases by difference of beat frequency `:....
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The most common oxidation state of an element is `-2`. The number of electrons present in the outermost shell is
Correct Answer - C Since the common oxidation state of metal is -2. This indictaes it is 2 electrons short of noble gas configuration. Therefore, it has six electrons in valence...
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If the charge of an experimental body and that of a gold- leaf electroscope are of the same nature, the divergence of the leaves of the gold-leaf elec
Correct Answer - increase
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Consider the following complex `[Co(NH_(3))_(5)CO_(3)]ClO_(4)` The coordination number, oxidation number number of d-electrons and number of unpaired
Correct Answer - A `[Co(NH_(3))_(5)CO_(3)]ClO_(4)` C.N. of Co = 6 , O.S. of `Co^(2+) is +3` It contain `Co^(3+)` as the centrl metal ion Co(Z = 27 ) : `[Ar^(18)]4s^(2)3d^(7)` `Co^(3+)...
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A compound with mlecular mass 180 is acylated with `CH_(3)COCl` to get a compound with molecular mass 390. The number of amino group present per molec
Correct Answer - C In acetylation, one H-atom (at mass = 1 amu) of `NH_(2)` group is replaced by an acetyl group, i.e., `CH_(3)CO` (mol mass = 43 amu) `-NH_(2)+CH_(3)COCl rarr...
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Instead of principal quantum number (n), azimuthal quantum number `(l)` & magnetic quantum number (m), a set of new quantum number s, t & u was introd
Correct Answer - B `{:(s = 1,t = 0,u = - (1)/(2)","(1)/(2),),(s = 2,t = 0,u = - (1)/(2)","(1)/(2),),(,t = 3,u = - 2"," -1"," 0","+1","+2 ,),(s = 3,t = 0,u...
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Instead of principle quantum number (n), azimuthal quantum number (L) &magnetic quantum number m, a set of new quantum number s, t & u was introduce w
Correct Answer - B S=1 t=0 `u=-1/2,1/2` No of subshell=1 , No of orbital=2 No of electrons =8 S=2 t=0,3 `u=-1/2,1/2`(for t=0) u=-2,-1,0,+1,+2(for t=3) No of subshell=2, No of orbital=7 No...
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Instead of principle quantum number (n), azimuthal quantum number (L) &magnetic quqntum number m, a set of new quantum number s, t & u was introduce w
Correct Answer - C S=1 t=0 `u=-1/2,1/2` No of subshell=1 , No of orbital=2 No of electrons =8 S=2 t=0,3 `u=-1/2,1/2`(for t=0) u=-2,-1,0,+1,+2(for t=3) No of subshell=2, No of orbital=7 No...
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In a nuclear reactor, the number of `U^(235)` nuclei undergoing fissions per second is `4xx10^(20).` If the energy releases per fission is 250 MeV, th
Correct Answer - B (B) the fission per second `=4xx10^(20)` So , the energy relased per second `=4xx10^(20) xx250MeV ` `=4xx10^(20) xx250xx10^(6) xx1.6xx10^(-19) J` therefore , energy relased in 10 h`=...
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Student while observing a slide of leaf section observed many stomata on the upper surface.
1. In a dicot leaf, stomata are generally absent on upper epidermis but are present on lower epidermis. Thus, the student must have thought that he has placed slide upside...
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