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6.022 x 1023 x 0.01 molecule is the answer

Molecular mass of CaCO3= 40 + 12 + (3 x 16) = 100 g [Molecular weight of Ca = 40, C = 12, O =16]

1 mole of Oxygen atoms = 6.022 x10^23 Oxygen atoms (Avogadro’s number)

1 mole of Calcium Carbonate = 100g of Calcium Carbonate

100 g of Calcium Carbonate (100,000mg of Calcium Carbonate) has 3 moles of Oxygen atoms = 3 x 6.022 x 10^23Oxygen atoms.

Thus, 1 mg of Calcium Carbonatehas (3 x 6.022 x 10^23)/100000 Oxygen atoms

At high temperature and low pressure, the gas volume is infinitely large and both intermolecular force as well as molecular volume can be ignored. Under this condition postulates of kinetic theory applies appropriately and gas approaches ideal behavior

at high temperature and low pressure the gas will behave ideally so 0.5 atm and 500Kis the best option.

Real gases show ideal gas behaviour at high temperatures and low pressures.

option 3

The gas constant R is 8.314 J / mol. K. Convert the numerical value of R so that its units are cal / (mol. K).

Values of R;0.082057 L atm mol-1 K-1;62.364 L Torr mol-1 K-1;8.3145 m3 Pa mol-1 K-1;8.3145 J mol-1 K-1*

i want b

ans is b according to first law of thermodynamic at constant volume(dQ)v=dU=500JW Q-U=0

Diamond is covalent,yetit hashigh melting point. ...Diamondhas a three-dimensional network involving strong C-C bonds, which are very difficult to break and hence it is thehigh melting point.

mg is the correct answer

(1)Na. elements be present in the same group as X

molecular formula of the chori de of an element is Na ( sodiyam ) . than reaction to sodiyam chloride

sodium(Na)is correct answer

option 1sodium Nais correct

correct answer is Na

mg has the highest melting point so mg is the correct answer

Option (1) is the correct answer

It is because diamond crystallize on what we call atomic crystal structure, which means that when it is in a solid state, there are atoms held together by strong covalent bonds. In diamond, every carbon atom connects with four more carbon atoms with single sigma bonds

in 1 mole of that substance... no. of moles of O are = (2*2+2) = 6 mole

so. in 0.3 moles.. the no.. of gram atoms are = 0.3*6 = 1.8

Henry's law is a gas law that states that the amount of dissolved gas is proportional to its partial pressure in the gas phase.

Positive deviations :

In these type of deviations,the partial vapour pressure of each component A and B of solution is higher than the vapour pressure calculated from Raoult's law,

For eg : Water and ethanol,chloroform and water.

In the case of positive deviation A-B interactions are weaker than those between A-A or B-B.This means that in such solutions molecules of A (or B) will find it easier to escape than in pure state.This will increase the vapour pressure and results in the positive deviation from Raoult's lawΔHmin=+ve

Negative deviations :

In this type of deviations,the partial vapour pressure of solutions is less than that of ideal solution of same composition.Boiling point of such a solution is relatively higher than the boiling points of both the components.This type of behavior is known as negative deviation.

Here the intermolecular attractive forces between A-A and B-B are weaker than those between A-B and leads to decrease in vapour pressure.

In case of solutions showing negative deviations,a slight decrease in volume and evolution of heat takes place on mixing

ΔVmix=−ve

moles = mass / molar mass

mass methane = 0.032 mg = 3.2x10^-5 g

moles methane = 3.2x10^-5 g / 16.042 g/mol

= 1.994x10^-6 moles methane

= 2.0x10^-6 moles

1 mole of anything is 6.022x10^23 units of that anything.

So 1 mole metane has 6.022x10^23 molecules of methane.

Thus molecules of methane = moles x 6.022x10^23 molecules / mol

= 1.994x10^-6 mol x 6.022x10^23 molecules/mol

= 1.2x10^18 molecules

Each glucose molecule is composed of C6H12O6. This means one mol of glucose contains 6 mol of oxygen. So 5 mol of glucose contains 5*6 = 30 mol of oxygen. As the chemical formula for glucose is C6H12O6, so the number of oxygen atoms in 5 moles of glucose is 30.

The relations known as Boyle's law, Charles' law, and Avogadro's law can be combined into an exceedingly useful formula called theIdeal Gas Equation,

A=wind speed , temparature, humidity ,surface area

The ability to resist breaking under tensile stress is one of the most important and widely measured properties of materials used in structural applications

example lead tin aluminium,etc

The capacity to bear weight is called tensile strength. Iron has tensile strength because it càn be used in making bridges,railway lines etc

1)it is important becauseIt is a quick way to detect problems in the material that you are purchasing.

It measures tensile strength. If your design needs a certain material tensile strength, you will know if this material will work for you.

You can get tensile modulus out of the test results. This can go into your design equations to see if the material will work for you.

You can get Poisson's Ratio, which is important for use in finite element analysis.

that's wrong

and also I want the answer of 2nd one

2)It has to do with the way light and electrons on the surface ofmetals interact. ...Metalis shiniest when it is first cut. Exposure to elements such as oxygen and carbon causemetalsto lose thelusteron the surface because the elements cause a tarnish that reduces the freedom of the electrons to vibrate.

Sulphur dioxide, Nitrogen oxides

Acid rain is one of the consequences of air pollution. It occurs when emissions from factories, cars or heating boilers contact with the water in the atmosphere. These emissions contain nitrogen oxides, sulfur dioxide and sulfur trioxide, which when mixed with water become sulfurous acid, nitric acid and sulfuric acid. This process also occurs naturally through volcanic eruptions.

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1)Although, glucose in its open chain structure contains a free aldehydic group yet it does not give 2,4-DNP test, a characteristic reaction of aldehydes, i.e. —CHO groups. This is because glucose actually exists in the cyclic hemiacetal form with only a small amount of the open chain form in equilibrium. Since, the concentration of the open chain form is very low and its reactions with 2,4-DNP are reversible, thus its 2,4-DNP adduct is generally not observed.

2)Both acidic (carboxyl) as well as basic (amino) groups are present in the same molecule of amino acids. In aqueous solutions, the carboxyl group can lose a proton and the amino group can accept a proton, thus giving rise to a dipolar ion known as a zwitter ion.

Due to this dipolar behaviour, they have strong electrostatic interactions within them and with water. But halo-acids do not exhibit such dipolar behaviour.

For this reason, the melting points and the solubility of amino acids in water is higher than those of the corresponding halo-acids

Sodiumis a chemical element withsymbol Na(from Latin natrium) and atomic number 11. ...Sodiumwas first isolated by Humphry Davy in 1807 by the electrolysis ofsodiumhydroxide.

2)The ElementSulfur--SulfurAtom. SI units & STP are used except where noted.Sulfur(sulphur) is a chemical element in the periodic table that has thesymbol Sand atomic number 16. ... It is an essential element in all living organisms and is needed in several amino acids and hence in many proteins.

Siliconis a chemical element (itssymbolin chemical formula expressions is "Si") that is present in sand and glass and which is the best known semiconductor material in electronic components. Its atomic number is 14. The most common isotope has atomic weight 28.

CCPstands for cubic closed packing , FCC is for face centered cubic structure andHCPis for hexagonal cubic packing . Now ,HCP and CCPare one of the forms in which a cubic lattice is arranged and FCC is one of the types of unit cells(in general

Nitrogen gas has complete octet for both the atoms and it is unreactive due to the prsence of strong triple bond.On the other hand phosphorous has bonds with unstable angle strains compared to that of nitrogen due to which it burns quickly,hence easily reacts.

p4 has angular strain . angle b/w 2 p atoms is 60o.so they tend to move away.

N2 has triple bond which makes it more stable.

Nitrogengas has complete octet for both the atoms and it is unreactive due to the prsence of strong triple bond.On the other hand phosphorous has bonds with unstable angle strains compared to that ofnitrogendue to which it burns quickly,hence easily reacts.

6.4g of sulphur:-Number of mole = weight/ atomic weight = 6.4/32 = 0.2 mole1 mole = 6.023*10^23 atomhence0.2 mole - 0.2*6.023*10^23 atom0.2 mole = 1.2046*10^23 atom

9.3g of phosphorus:-Number of mole = weight/ atomic weight = 9.3/30.9 = 0.3mole1 mole = 6.023*10^23 atomhence0.3 mole =0.3*6.023*10^23 atom0.3mole = 1.806*10^23 atom

so, 9.3g of phosphorus has more no. of atoms

Non-metals are stored in water. Phosphorusis a very reactive non-metal. It catches fire if exposed to air. To prevent the contact ofphosphoruswith atmosphericoxygen, it is stored in water.option c

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Moles of Na2CO3= mass/molar mass = 25.3/106 = 0.239 molesMolarity of Na2CO3solution = number of moles/ volume in lire = 0.239/0.25 (250ml = 0.25 L) = 0.955 MNow, 1 mole of Na2CO3contains 2 moles of Na+and 1 mole of CO32-ions.Therefore,Concentration of Na+= 2 x 0.955M = 1.91MConcentration of CO32-= 1 x 0.955M = 0.955M

Washing soda or soda ash

3381=3*11271127=7×1617*23=161

3381 ×2=6762=x161×7=1127=middle box161÷7=23=last box

(a)carbon dioxide (b) sulphate (c) oxygen (d) heliume

carbondioxide,sulphate,oxygen,hydrogen or heliume

Summaryof Common Properties

High ionization energies.

High electronegativities.

Poor thermal conductors.

Poor electrical conductors.

Brittle solids—notmalleableorductile.

Little or no metallicluster.

Gain electrons easily.

Dull, not metallic-shiny, although they may be colorful.

As we go down the group the atomic number increases and it changes from nonmetals to metals. Elements of group 14 like Carbon and silicon exhibit the characteristics of non-metals. Germanium possesses intermediate characteristics of metals and non-metals i.e. metalloids and tin and lead are metals. The appearances and structures prove the metallic characteristics of these elements.

2Ag+S→Ag2S107×232g246g=214gtherefore,32gSreactswith=214gofsilver5gSreactswith=(214/32×5)gofsilver=1.3375gofsilverTherefore,massofAg2Sformed=(1+1.3375)g=2.3375g

Sodium is a metal for its property of donating an electron.

4Na + O2 -------> 2Na2O

Forms,

Sodium Oxide.

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The two extreme cases ofchemicalbonds are:Covalent bond:bondin which one or more pairs of electrons are shared by two atoms.Ionic bond:bondin which one or more electrons from one atom are removed and attached to another atom, resulting in positive and negativeionswhich attract each other.

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Sodium Bicarbonate is a polar compound. The sodium (Na) creates a + charge, and the bicarbonate (HCO3) will create a - charge.

This is an ionic bond.

(a) is correct option

As studying the Modern periodic table, The group 17 contains the members of the halogen family.

All of them have the general formula X2. A gradation is observed in their physical state down the group.

Thus, fluorine (F2) and chlorine (Cl2) are gases. Bromine (Br2) is a liquid while iodine (I2) is a solid.

sayd se A wala opstion right he

The reaction of methanol with phenyl magnesium bromide is:

CH3OH + C6H5MgBr → C6H6+ Mg(OCH3)Br

Amixture of benzene and Mg(OMe)Br is obtained.

The correctoption is A.

option B ) a mixture of benzene and Mg(OMe)Br