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100 moles of sulphur is required to produce 100 moles of h2so4100×32.06=3206g

correct answer is 3206 g

Allotropy, the existence of a chemical element in two or more forms, which may differ in the arrangement of atoms in crystalline solids or in the occurrence of molecules that contain different numbers of atoms. ... Elements exhibitingallotropyinclude tin, carbon, sulfur, phosphorus, and oxygen.

what is your question

option A is the correct answer

3-ethyl-3-methyl-octane

1

2

ilu

option b is correct.. because gold number is inversely proportional to protective powers

Though hydrogenis a non-metal, it has been placed at the top of group 1 above the alkali metals because its electronic configuration is similar to alkali metals i.e. (have 1 valence electron in the outermost shell).

the correct ans is .08 gm.

let the weight kclo3 be x weight of kcl is 7-x

equation

kclo3----kcl+.1.502

inital mole of kclo3 formed is cpmpletly used to form 1.5 mole of o2

threfore x/122.5 ×1.5=2.5/32

x=6.38

wt of kccl=7-6.38gm=.61 gm

fraction =..08

when the reaction is reversed , the value of kp for the reversed reaction becomes reciprocal of the actual kp

so, kp of 2nd reaction is = 1/51

you can write a project with blue or black. or colourful pens

Steps

Identify the purpose for your work plan. Work plans are written for various reasons. ...Write the introduction and background. ...Determine your goal(s) and objectives. ...Consider ordering your work plan by "SMART" objectives. ...List your resources. ...Identify any constraints. ...Who is accountable. ...Write your strategy

oh thank u very much

hi pratibha

In physics, the proton-to-electron mass ratio, μ or β, is simply the rest mass of the proton divided by that of the electron.

Ratio = 1/108and it has no units as it gets cancelled

The arrangement of positive ions in an atom is called lattice

Lattice energy is a type of potential energy that relates to the stability of ionic solids. Ionic solids are very stable, which means that it takes a lot of energy to break their bonds.

The14 Bravais latticesare grouped into sevenlatticesystems: triclinic, monoclinic, orthorhombic, tetragonal, rhombohedral, hexagonal, and cubic. ... A crystal family is determined bylatticesand point groups. It is formed by combining crystal systems which have space groups assigned to a commonlatticesystem.

you can go in golden

A space lattice is an array of points showing how particles (atoms, ions or molecules) are arranged at different sites in three dimensional spaces.

Unit cell is the smallest repeating unit in space lattice which, when repeated over again, results in a crystal of the given substance.

Space lattice can be defined as a regular, periodic, repeated three dimensional array of points. Unit Cell. A unit cell is The Simplest Repeating Unit in a Crystal. It is the smallest volume of the crystal with which entire crystal can be constructed by translational repetition in three dimensions.

“Aspace latticeis an array of points showing how particles (atoms, ions or molecules) are arranged at different sites in three dimensional spaces.” ... Theunit cellmay bedefinedas, “the smallest repeatingunitinspace latticewhich, when repeated over again, results in acrystalof the given substance”

1.a space lattice or crystal lattice is defined as a regular three dimensional arrangement of identical points in space or it can be defined as an array of points showing how molecules, atoms or ions are arranged at different sites in three dimensional space.

2. A unit cell is the most basic and least volume consuming repeating structure of any solid. It is used to visually simplify the crystalline patterns solids arrange themselves in. When the unit cell repeats itself, the network is called a lattice.

The simple cubic has a coordination number of 6 and contains one atom per unit cell.

the smallest group of atoms which has the overall symmetry of a crystal, and from which the entire lattice can be built up by repetition in three dimensions.

i) 4 lattice points.ii) One unit cell of a face-centered cubic has 8 lattice points are corners and 6 lattice points at faces, total 14 lattice points.iii) 2 lattice points.

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Simple cubic is the correct answer

I too got the same answer but in the key it is given as option (d)

Allotropy is the property by virtue of which an element exist in more than one form and each form has different physical properties but identical chemical properties. These different forms are called allotropes. The two common allotropic forms of carbon are diamond and graphite.

Carbon exists in two allotropic forms:(1) CRYSTALLINE FORM(2) AMORPHOUS FORM

CRYSTALLINE FORMS

There are three crystalline forms of carbon:(1) Diamond(2) Graphite(3) Bucky ball

AMORPHOUS FORMS

There are various amorphous forms of carbon such ascoalcokecharcoallampblackgas carbon etc.

DIAMOND

In diamond, each C-atom is covalently bonded to four other C-atom to give a tetrahedral unit. In diamond each C-atom is sp3-hybridized.Therefore each C-atom forms four sigma bonds withneighbouringC-atoms.In diamond C-C-C bond angle is 109.5O.These basic tetrahedral units unite with one another and produce a cubic unit cell.C-C bond length in diamond is 1.54AO.C-C bond energy is 347 kj/mole.In diamond crystal, basic units joined to forms octahedral shape of diamond crystal.

PROPERTIES OF DIAMOND

In diamond each C-atom utilizes its four unpaired electrons in bond formation. These bonding electrons are localized. Due to this reason diamond is a bad conductor of electricity.Diamond is the hardest substance ever known.Pure diamond is cloudless.Its melting point is 3500OC.

Pure diamond is transparent to x-rays.It has high refractive index i.e. 2.45.Due to impurities it may be colored.Its density is 3.5 gm/cm3.

GRAPHITE

In graphite each C-atom is covalently bonded to three C-atom to give trigonal geometry. Bond angle in graphite is 120O. Each C-atom in graphite is sp2-hybridized. Three out of four valance electrons of each C-atom are used in bond formation while the forth electrons free to move in the structure of graphite. Basic trigonal units unite together to give basic hexagonal ring. In hexagonal ring C-C bond length is 1.42AO. In graphite these rings forms flat layers. These layers are arranged is parallel ,one above the other. These layers 3.35AOapart and are held together by weak van der waals forces only.These layers can slide over one another.Thus it is very soft. Forth electron of each c-atom forms delocalized

p-system.

PROPERIES OF GRAPHITE

It is dark gray, have dull metallic luster.It is soft and greasy.It is used as lubricant.Its density is 2.2 gm/cm3.It is used in the preparation of electrodes as it canduct electricity.It is used as "pencil lead".It is used as moderator in nuclear reactors.

C3h8+5o2=3co2+4h20so 1moleof proparne require 5 mole of o2(stochiometrically) now convert them into liters1*22.4 propane will give5*22.4therefore 1l will give 5l

In 1gm of hydrogen is 1

we have formula no. of moles=given wt of atom/atomic wt of atom=> no. of moles = 1 /1=> no.of moles = 1now another formula is no. of moles = no. of atoms /avogadros constant

=> 1 = no. of atoms /6.022×10^23so no. of atoms in 1 gram of hydrogen = 6.022×10^23 atoms

Ans :- 7

So... for the element of NITROGEN, you already know that the atomic number tells you the number of electrons. That means there are7electrons in a nitrogen atom.

Yup

In atomic physics, the Rutherford–Bohr model or Bohr model or Bohr diagram, introduced by Niels Bohr and Ernest Rutherford in 1913, Bohr behn ka lund tha depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar to structure of the Solar System, but with attraction provided by electrostatic forces rather than gravity. After the cubic model (1902), the plum-pudding model (1904), the Saturnian model (1904), and the Rutherford model (1911) came the Rutherford–Bohr model or just Bohr model for short (1913). The improvement to the Rutherford model is mostly a quantum physical interpretation of it. The model's key success lay in explaining the Rydberg formula for the spectral emission lines of atomic hydrogen. While the Rydberg formula had been known experimentally, it did not gain a theoretical underpinning until the Bohr model was introduced. Not only did the Bohr model explain the reason for the structure of the Rydberg formula, it also provided a justification for its empirical results in terms of fundamental physical constants.

The Bohr model is a relatively primitive model of the hydrogen atom, compared to the valence shell atom. As a theory, it can be derived as a first-order approximation of the hydrogen atom using the broader and much more accurate quantum mechanics and thus may be considered to be an obsolete scientific theory. However, because of its simplicity, and its correct results for selected systems (see below for application), the Bohr model is still commonly taught to introduce students to quantum mechanics or energy level diagrams before moving on to the more accurate, but more complex, valence shell atom. A related model was originally proposed by Arthur Erich Haas in 1910, but was rejected. The quantum theory of the period between Planck's discovery of the quantum (1900) and the advent of a full-blown quantum mechanics (1925) is often referred to as the old quantum theory.

Mass of one atom of helium (He) = 4 amu(atomic mass unit)

100 amu of He = 100/4 = 25

So, 25 atoms are there in 100 amu of He.

100amu of he=100/4=25so 25 atoms

The equilibrium for the saturated solution is

PbI2 (s) <=> Pb2+ (aq) + 2 I- (aq)and the equilibrium condition is given byKsp = [Pb2+][I-]^2

at equilibrium[Pb2+]= 1.5 x 10^-3 M[I-]= 2 x 1.5 x 10^-3=3.0 x 10^-3 M

Ksp = 1.5 x 10^-3 ( 3.0 x 10^-3)^2 =1.4 x 10^-8

Rancidity: It is defined as chemical decomposition of oils and fats which in another words is spoiling food materials that difficult for consumption.It can be prevented by following methods:(i) The packing of food materials should be replaced the air with Nitrogen.(ii) The food materials should be placed at very low temperatures.

In haloarenes the bond between the halogen and the benzene ring is not a single It has a partial double bond character due to resonance.Thusthe attack of the nucleophile becomes more difficult in a haloarene than a haloalkane.

The relative energies of molecular orbitals depend upon the following two factors:

(i) Atomic orbitals energies for the combination to form molecular orbitals.

(ii) The extent of overlapping between the atomic orbitals.

The greater the overlap, the more the bonding orbital is lowered and the anti-bonding orbital is raised in energy relative to atomic orbitals. For e.g., the extent of overlapping in case of sigma – orbital is more than that in pi – orbital. Consequently, the energy of a σ2pzis lower than the energy of bonding π2pxor π2pyMOs.

Now, 1s atomic orbitals of two atoms form two molecular orbitals designated as σ1s and σ*1s. The 2s and 2p orbitals (eight atomic orbitals on two atoms) form four bonding molecular orbitals and four anti-bonding molecular orbitals as:Bonding MOs:σ2s, σ2pz, π2px, π2py

Anti-bonding MOs:σ*2s, σ*2pz, π*2px,π*2py

The energy levels of these molecular orbitals have been determined experimentally by various methods. The order of increasing energy of molecular orbitals obtained by the combination of 1s, 2s and 2p orbitals of two atoms is:

s1s, s*1s, s2s, s*2s, s2pz, p2Px= p2py, p*2px= p*2py, s*2pz

Energy increases ———————————->

But for molecules O2onwards (O2, F2), the first order of energies of MOs is correct.Thus, for diatomic molecules of second period (Li2to Ne2), there are two types of energy levels of Mos. For molecules Li2, Be2, B2, C2and N2the molecular orbital energy level diagram