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Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.

At STP 22.4L of any gas (assuming its ideal nature)≡ 1g-molecular i.e. 1mole of that gas

here2.24 L of volume at STP≡ 4.4g ∴ 22.4Lof volume at STP≡ 44gSo, molecular mass of the gas is 44g/molThe gas may be CO2, C3H8(Propane)

hence, option (a) is correct

but how 22.4L of volume at STP=44g

24

24 is the correct answer

CS2 + 3O2 ----heat----→ CO2 + 2SO2

this is a oxidisation reaction as well as combustion reaction

when the reaction take place it then it become in gas so co

cs2+302___heat__co2+2soc...............

It is mainlyusedin the industrial manufacturing of compounds such as ammonia, calcium cynamide etc.

It isusedin the manufacturing industries such as iron and steel to obtain an inert atmosphere.

Liquid nitrogen isusedin food industries as a preservative and as a refrigerant

Uses of Dinitrogen:

It is mainlyusedin the industrial manufacturing of compounds such as ammonia, calcium cynamide etc.

It isusedin the manufacturing industries such as iron and steel to obtain an inert atmosphere.

Liquid nitrogen isusedin food industries as a preservative and as a refrigerant.

Uses of Dinitrogen:

It is mainlyusedin the industrial manufacturing of compounds such as ammonia, calcium cynamide etc.

It isusedin the manufacturing industries such as iron and steel to obtain an inert atmosphere.

Liquid nitrogen isusedin food industries as a preservative and as a refrigerant.

Uses of Dinitrogen:

It is mainlyusedin the industrial manufacturing of compounds such as ammonia, calcium cynamide etc. It isusedin the manufacturing industries such as iron and steel to obtain an inert atmosphere. Liquid nitrogen isusedin food industries as a preservative and as a refrigerant

Dinitrogenmakes up to 78% of the earth’s atmosphere and it is the most abundant element present in the air and the seventh most abundant uncombined element found in the universe.This element was first discovered in the year 1772 by a Scottish physician Daniel Rutherford.The symbol of this chemical element is N and 7 is its atomic number.

Uses of Dinitrogen:

It is mainlyusedin the industrial manufacturing of compounds such as ammonia, calcium cynamide etc. It isusedin the manufacturing industries such as iron and steel to obtain an inert atmosphere. Liquid nitrogen isusedin food industries as a preservative and as a refrigerant

Uses of Dinitrogen:

It is mainlyusedin the industrial manufacturing of compounds such as ammonia, calcium cynamide etc.

It isusedin the manufacturing industries such as iron and steel to obtain an inert atmosphere.

Liquid nitrogen isusedin food industries as a preservative and as a refrigerant

For first order reaction,

half life = ln2/k=> K = ln2/(t½) = 0.693/100 = 6.93 × 10-³per sec

option C

Moles of glucose = 18 g/ 180 g mol–1 = 0.1 molNumber of kilograms of solvent = 1 kgThus molality of glucose solution = 0.1 mol kg-1For water, change in boiling pointÄTb = Kb × m = 0.52 K kg mol–1× 0.1 mol kg–1= 0.052 KSince water boils at 373.15 K at 1.013 bar pressure, therefore, the boiling point of solution will be 373.15 + 0.052 = 373.202 K.

a) orbital with quantum number l=2 is clover leaf with subshell db)

1. a

1. b

2

ph=-logC =-log0.06 =1.22

is the correct answer pH = 1.22

thank you

option a

Atomic weight of X =30 and Y =20Molecular weight of that compound = 120

Hence, theMolecular formula of that compound is X2Y3

( 2*30+ 3*20 = 60+60=120)

a compound with particular chemical properties including turning litmus blue and neutralizing or effervescing with acids; typically, a caustic or corrosive substance of this kind such as lime or soda.

l am liked Your answer like my answer

a chemical substance that reacts with acid to form a salt. an ankali has a pH value of more than 7.

In chemistry, analkali(/ˈælkəlaɪ/; from Arabic: al-qaly "ashes of the saltwort") is a basic, ionic salt of analkalimetal or alkaline earth metal chemical element. Analkalialso can be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0.

the product is

it includes the statement that the chemical and physical properties of the elements recur periodically when the elements are arranged in the order of their atomic weights. There areafew elements still missing, according to theperiodic lawwhich has been so valuable in chemistry.

HERE ARE SOME DRAWBACKS OF MENDELEEVS PERIODIC TABLE

Position of hydrogen:-hydrogen resembles both, alkali metals (IA) and the halogens (VIIA) in properties so Mendeleev could not decide where to place it.

2. Position of Isotopes:- As atomic weight of Isotopes differ, they should have been placed in different position in Mendeleev's periodic table. But there was no such places for Isotopes in his table.

3. Cause of periodicity:- Why physical and chemical properties repeated in a group.

4. Anamolous pairs of elements:- There were some pair of elements which did not follow increasing order of atomic weights.

Example: Ar&K, Te&I, Co&Ni, Th&Pa

5. Gaps in his period table:- Mendeleev left several gaps in his periodic table, proposing that some of the elements were still undiscovered

Example: Eka Aluminium - Gallium(Ga), Eka Silicon - Germanium(Ge), Eka Boron - Scandium(Sc), Eka Mangenese - Technetium(Tc).

6. Like elements were placed in different groups.

Example: Platinum (Pt) and Gold(Au) have similar properties but were placed in different groups Pt(VIII) and Au(IB).

7. Unlike elements were placed in same groups.

Example: Cu, Ag and Au were placed in Ist group with Na, K etc while they differ in their properties.

8. It was not clear that lanthanides and Actinides are related with IIIA group or IIIB group.

The termchlor-alkalirefers to the two chemicals (chlorineand analkali) whichare simultaneously produced as a result of the electrolysis of a saltwater. The most commonchlor-alkalichemicalsare chlorineand sodium hydroxide (caustic soda) butcaninclude potassium hydroxide and muriatic acid.

In an emulsion, oneliquid(the dispersed phase) is dispersed in the other (thecontinuousphase).

Depending upon the nature of the dispersed phase, the emulsions are classified as;

(i)Oil-in-water emulsions(O/W):The emulsion in which oil is present as the dispersed phase and water as the dispersion medium(continuous phase)is called an oil-in-water emulsion. Milk is an example of the oil-in-water type of emulsion. In milk liquid fat globules are dispersed in water. Other examples are, vanishing cream etc.

(ii)Water-in-oil emulsion(W/O):The emulsion in which water forms the dispersed phase, and the oil acts as the dispersion medium is called a water-in-oil emulsion. These emulsion are also termedoil emulsions. Butterandcold creamare typical examples of this types of emulsions. Other examples are cod liver oil etc.

The shock from a car battery will not kill you. In fact, under normal conditions, a 12-volt car battery will usually not even shock you. Car batteries are not harmless, though. There are many ways you can be injured by car batteries:

The shock from a car battery will not harm you. Public Domain Image, source: Christopher S. Baird.Car battery acid can leak out of the battery and burn your skin.If a flame or spark is brought too close to a car battery with improper ventilation, hydrogen gas from the battery can explode, splashing battery fragments and acid all over your skin.Sparks (arcing) between a car battery terminal and other metal parts can cause the metal to get hot enough to burn you.If a car battery is short-circuited by a cable, the cable can heat up enough to catch fire.There are enough dangers present that it is a good idea to be cautious around car batteries and follow the maintenance instructions in the car's manual, even though electrocution by car battery is not going to happen.

Best bro best answer thanks a lot..

Black substance in the lead pencil is graphite is non metal but contact electricity like those of carbon brush of drills.Graphite is carbon of lead element which handle heat fire and electric contacts,soft like talc and smooth

graphite,it is non metal

Acolourlessliquid substance that is acyclictrimerofacetaldehyde: used in makingdyestuffsand as ahypnoticandanticonvulsantdrug. Formula: (C2H4O)3

Word origin of 'paraldehyde'

para+aldehyde

para means 1.beside; near2.beyond3.resembling

Spectrum, in optics, the arrangement accordingtowavelength of visible, ultraviolet, and infrared light. ...Spectramay beclassifiedaccordingtothe nature of their origin, i.e., emission or absorption.

AUTOTROPHIC NUTRITION1. It means that the organism prepare its own food and is not dependent on any other organism.2.Food is prepared from CO2, water and sunlight.3. All green plants and some bacteria have this type of nutrition.

HETEROTROPHIC NUTRITION1. it means that the organism does not prepare its own food and dependent on other organism for food.2. Food is obtained from other organisms3. All animals and fungi have this type of nutrition.

‘Forbidden zone' in reference to band theory of solids:-According to bond theory, forbidden zone is the energy gap between valence band and conduction band in solids.This gap is large in insulators and small in semi-conductors.There is no forbidden zone in metals, because in metals valence and conduction band overlapForbidden zone is the energy gap. It is the gap between the valence band and conduction band in the band theory.

The half life of a first order reaction is given by the equation,t(1/2) = 0.693/kWhere “k” is the rate constant.From the equation, we can calculate the rate constant.100= 0.693/kk = 0.693/100= 0.00693sec^(-1)Now, use the equationk= (2.303/t)log(initial conc./final conc.)After consuming 80% of the reactant, the final concentration will be 20% of the initial concentration.Assume, initial concentration is xFinal concentration is 20% of x = (20/100)x = 0.2xThereforeInitial conc./final conc. = x/0.2x = 5Substitute this in the above formula0.00693 = (2.303/t)log(5)0.00693= 2.303×0.698/tt = 231.96 secs.Therefore it takes 231.96 secs. to consume 80% of the reactant.

D. Selenium

Explaination : Seleniumis a very rare mineral. It is scarce wherever it is found and it is not found too often. The color is a distinctive red-gray with a metallicluster. T

In gaseous and molten state, it is a neutral molecule and its is PCl5 triagonal bipyramidal. This triagonal bipyramidal structure is present in non-polar solvents such as CS2and CCl4. However, In the solid state PCl5 exists as [PCl4]+and [PCl6]-, therefore, it is ionic in nature.

Nitric acid is HNO3so molecular mass is 63H composition 1/63*100=1.58%N composition 14/63*100=22.22%O3 composition 48/63*100=76.20%

Characteristics of liquid state :

1. They have fixed volume but no fixed shape.

2. They show fluidity.

3. They have relatively weaker intermolecular forces between them (in comparison with solids).

1. physical change2. chemical change3. physical change4. chemical change

thanks for sending the answers

1- have fixed vol and mass2- intermolecular forces are strong and distance are short.3- tightly packed particles

The molecules, atoms or ions insolidsare closely packed, i.e., they are held together by strong forces and cannot move about atrandom. Thussolidshave definite volume, shape, slow diffusion, low vapour pressure and possess the unique property of being rigid. Suchsolidsare known as truesolids.

658g in this answer key of success

658 is the correct answer

bhaiya can you answer my question also

Ethylene glycol is termed as the primary ingredients in antifreeze.The ethylene glycol molecular formula is C₂H₆O₂.Molar mass of C₂H₆O₂ is = (2×12) +(6×1) + (216) = 62g/molNow that antifreeze by mass is 50%, then there is 1kg of ethylene glycol which is present in 1kg of water.ΔTf = Kf×mΔTf = depression in the freezing point.= freezing point of water freezing point of the solution= O°c - Tf= -TfKf = depression in freezing constant of water = 1.86°C/mM is the molarity of the solution.=(mass/molar mass) mass of solvent in kg=1000g/62 (g/mol) /1kg=16.13mIf we plug the value we get-Tf = 1.86× 16.13 = 30Tf = -30°c

sea water and soda water are the solutions.

soil and soda water are the solution of mixture

Fresh water freezes at32 degrees Fahrenheitbut seawater freezes at about28.4 degrees Fahrenheit, because of the salt in it. When seawater freezes, however, the ice contains very little salt because only the water part freezes. Seawater contains sodium chloride (common salt). Salt dissolves in water, but does not easily attach to ice. Since some of the water molecules are replaced by salt, the ice grabs less water molecules. This upsets the rate of freezing and melting water molecules. Melting is happening faster than freezing.

An iron object becomescoatedin atoms of a lessreactivemetal. As the new metal is lessreactive, it is slower to corrode. This process is common with gold, silver, nickel, copper and tin as they are low down in the reactivity series. For instance, tin cans are actually steel (containing iron)coatedin tin.

Water is the enabler offastoxidation ofironso freshwater will also causerust. However,salt wateris a very good conductor (lots of dissociated ions) and so there are a number of electrolysis reactions that tremendously acceleratecorrosioninsalt water.

THE ANSWER IS ALTERNATING CURRENT MOTOR

armateur

tetravalency and catenation are the two properties

yes right question................,...................