Explore topic-wise InterviewSolutions in .

Given:molecular mass=40 g/molvolume of solution= 500ml=0.5 litermass of NaOH=10gFormula: no of moles= given mass/molecular massmolarity=no of moles/volume of solution in literSolution:no of moles=10/40=0.25 molmolarity=0.25/0.5=0.5MTherefore molarity=0.5M

14) ... the basicity is 3 , it can donate 3 H+

15) ... no. of moles = 2/40 = 0.05 option C)

Concentration is equal(mass/molar mass)*(1000/volume of solution)

There are an infinite number of fundamental colors, if by "fundamental" you mean "spectral". Spectral colors are also known loosely as rainbow colors. A spectral color is composed of a single fundamental color on the visible part of the electromagnetic spectrum, as opposed to a mixture of colors. Spectral colors such as red or green are composed of light waves of a single frequency. Non-spectral colors such as brown and pink are composed of a mixture of spectral colors. Simple lasers, by their very nature, only emit one frequency of light (to an excellent approximation). This means that simple lasers can only generate spectral colors (compound colors from laser systems can be made by mixing the light from several lasers, or by running the spectral color through a material that converts it to a mixture of colors). Even though the spectral colors are a subset of all colors, there are still an infinite amount of spectral colors. This fact becomes obvious when looking at the spectrum from a prism, which is simply a spread of spectral colors.

(3) Law of multiple proportionsThis shows that the weights of lead combing with field weight of oxygen are in the ratio 1/2:1 or 1:2 which is in accordance with law of multiple proportions.

how

This law which was proposed by Ritcher (1792) states that “when two elements combine separately with a fixed mass of the third element then the ratio of their masses in which they do so is either the same or some whole number multiple of the ratio in which they combine with each other”.For example Carbon, Sulphur and Oxygen form CO2, SO2, and CS2. In 12 parts by mass of carbon combine with 32 parts by mass of oxygen while in SO232 parts by mass of Sulphur combine with 32 parts by mass of oxygen. The ratio of masses of carbon and sulphur which combine with a fixed mass of oxygen is 12: 32 or 3: 8.

(d) law of multiple proportions

Law of multiple proportions, statement that when two elements combine with each other to form more than one compound, the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.

Thanks

Molality ofH2SO4=?H2SO4=?

n1n1= number of moles ofH2OH2Oandn2n2= number of moles ofH2SO4H2SO4.

Molality ofH2SO4H2SO4means the number of moles ofH2SO4H2SO4present in1000g1000gof water

g.mol wt of water(H2O)=2×1)+16=18g(H2O)=2×1)+16=18g

Mole fraction ofH2OH2Oin solution=0.85=0.85

Mole fraction ofH2SO4H2SO4in solution=1−0.85=0.15=1−0.85=0.15

n1n1= no of moles ofH2OH2O

=wt.of.H2Og.mol.wt.ofH2O=wt.of.H2Og.mol.wt.ofH2O

=100018=100018

=55.55=55.55

n2n2= no of moles ofH2SO4=?H2SO4=?

Mole fraction ofH2SO4=n2n1+n2H2SO4=n2n1+n2

0.15=n255.55+n20.15=n255.55+n2

or0.15(55.55+n2)=n20.15(55.55+n2)=n2

orn20.15n2+8.3325n20.15n2+8.3325

n2=9.8n2=9.8

Molality =9.8 m

or Molality ofH2SO4=xH2SO4xH2O×1Mol.wt.ofH2OH2SO4=xH2SO4xH2O×1Mol.wt.ofH2O×1000×1000

=1−0.850.85=1−0.850.85

0.15×118×0.15×118×10001000=9.8m

actually it not too long for class 11 student ...I can't understand this properly

solution is of 1litre and 0.5 Mso amount of H2SO4 present is 0.5*1=0.5

Compounds are made up of atoms of different elements. ... Thelaw of multiple proportions,statesthat when two elements combine to form more than one compound, the mass of one element, which combines with a fixed mass of the other element, will always be ratios of whole numbers.

Thelaw of multiple proportions, states that when two elements combine to form more than one compound, the mass of one element, which combines with a fixed mass of the other element, will always be ratios of whole numbers.

Let’s take 56 g of iron and heated it with 32 g of sulphur. It will form 88 g of iron sulphide (both iron and sulphur will completely react with each other to form 88 g ferrous sulphide). In a closed system the mass of the reactants must equal the mass of the products any chemical process. Hence the law implies that mass cannot be created or destroyed, although it may be rearranged and changed into different types of particles.

21% w/v H2SO4 means 21 g of H2SO4 is present in 100 ml of solution.

No. of equivalents of H2SO4 = weight / Gram equivalent of H2SO4= (21 / 49) moles

Normality = (Equivalents × 1000) / Volume of solution= [(21 / 49) × 1000] / 100= 4.28 N

Not 21% but ok i have understood.Thanks.

The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as system's mass cannot change, so quantity cannot be added nor removed. Hence, the quantity of mass is conserved over time.

the answer is c)1.5N

In chemistry, the law of multiple proportions is one of the basic laws of stoichiometry used to establish the atomic theory, alongside the law of conservation of mass and the law of definite proportions.There are compounds made up of the same elements, like carbon monoxide (CO) and carbon dioxide (CO2). Both compounds are made of carbon (C) atoms and oxygen (O) atoms; however, the ratios of carbon and oxygen in each compound is different. This illustrates thelaw of multiple proportions.

Thelaw of multiple proportions,statesthat when two elements combine to form more than one compound, the mass of one element, which combines with a fixed mass of the other element, will always be ratios of whole numbers

Thelaw of conservation of massstates that in a closed system, the mass of the system cannot change over time. Look at our example of the candle in the closed room. Though much of the wax itself is no longer present in its original form, all of the mass of the wax is still present in the room, albeit in a different form.

The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.

No. of moles of atoms = weight / atomic weight.

100 gms of N₂ = 100/2 x 14 moles = 100/28 moles

Number of molecules = 100 / 28 x 6.022 x 10²³

Molar mass of N₂ = 2 x molar mass of monoatomic N

Molar mass of N₂ = 2 x 14.0067 = 28 moles.

Number of molecules = 100/28 x 6.022 x 10²³

No. of atoms = 2 x 100/28 x 6.022 x 10²³ = 43.01 x 10²³

For NH₃ :-

100 gm of NH₃ = 100/17 moles

Number of molecules = 100/17 x 6.022 x 10²³ molecules

No. of atoms in NH₃ = (1 + 3) = 4 x 100/17 x 6.022 x 10²³ =141.69 x 10²³ atoms.

Therefore, NH₃ has more atoms than N₂.

No. of moles of atoms = weight / atomic weight.

100 gms of N₂ = 100/2 x 14 moles = 100/28 moles

Number of molecules = 100 / 28 x 6.022 x 10²³

Molar mass of N₂ = 2 x molar mass of monoatomic N

Molar mass of N₂ = 2 x 14.0067 = 28 moles.

Number of molecules = 100/28 x 6.022 x 10²³

No. of atoms = 2 x 100/28 x 6.022 x 10²³ = 43.01 x 10²³

For NH₃ :-

100 gm of NH₃ = 100/17 moles

Number of molecules = 100/17 x 6.022 x 10²³ molecules

No. of atoms in NH₃ = (1 + 3) = 4 x 100/17 x 6.022 x 10²³ =141.69 x 10²³ atoms.

Therefore, NH₃ has more atoms than N₂.

When a metal is dropped in water, it reacts with water instantly or in the addition of heat and forms an oxide and a colourless gas is evolved. Some metals can even be explosive on reaction with water.

Gas evolved - hydrogen.Tests:-1.Burns with a pale blue flame.2.Burns with a pop sound.

Please hit the like button if this helped you

Factors of 27: 1, 3, 9, 27. Prime factorization: 27 = 3 x 3 x 3, which can also be written 27 = 3³.

Any Matter that is made up of two elements is a compound , and water is made up of two elements H and O having formula as H2O

So, it is a compound.

80 is the correct answer of this question

Becauserust isa very specific compounds - hydratediron(III) oxide. Many metals form oxidesbutnone "rust" likeiron does. ...Rust will corrodethemetal but Gold isa noblemetal notaffected easily by air, acids and alkalies. This yellowmetal willremain likegoldalways unaffected by oxygen.

Iron when reacted with both water and oxygen which present in air (moist air), corrodes. Its silvery colour changes to a reddish-brown, because hydrated oxides are formed which is commonly called as rust.Reaction showing formation of rust when reacted with water in presence of oxygen (atmosphere).4Fe + 3O₂+ XH₂O → 2Fe₂O₃.XH₂O

Mass no of Oxygen is 8and sulphur is 16

Rusting of iron articles is faster in coastal areas because in coastal areas ,air contains high percentage of moisture because of sea or ocean ,when the moisture on high percentage then the iron article has take more water vapour (H2O) and oxygen (O2) when rusting take place faster

Ans :- Use SOCl² , then Rosenmund's Red. by PD/BaSO⁴

anode will be the electrode considered as a positive terminal in a cell and cathode is negative terminal

anode is considered as positive terminal of a cell this is due to flow of charge.

Kindly provide all the statements.

pH + pOH = 14.pH is a figure expressing the acidity or alkalinity of a solution on a logarithmic scale on which 7 is neutral, lower values are more acid and higher values more alkaline. The pH is equal to −log10 c, where c is the hydrogen ion concentration in moles per litre.

Ozonolysisistheprocess by which ozone (O3) reacts with alkenes (olefins) to breakthedouble bond and form two carbonyl groups. Ifthedouble bond ofthealkene is substituted with hydrogen or carbon atoms,thecarbonyl groups that are formed are either aldehydes or ketones

Electrolysis, or electrolytic refining, is a technique used for extraction, as well as purification, of metals obtained by any refining method. In the electro refining process, a block of impure metal becomes the anode, and a thin sheet of metal becomes the cathode.

Steric effects are nonbonding interactions that influence the shape and reactivity of ions and molecules. Steric effects complement electronic effects, which usually dictate shape and reactivity. Steric effects result from repulsive forces between overlapping electron clouds

metamerism.

Why not functional.???

sry it's of biology

Forests are biodiversity hot spot. The measure of the biodiversity of an ares is the no. of species found there.A forest being home for range of different life forms from a tiny microorganismsfungi to animals like lions ,deer etc. and hence called biodiversity hotspots.

(i). n=m/M =52/4 =13 moles.(ii). 1 mole of He= 6.022 x 10^23 1 atom of He= 1/6.022 x 10^23So, 12.044 x 10^23 atoms of He = 12.044 x 10^23/ 6.022 x 10^23 = 2 moles.

formalin is aqueous solutions of formaldehyde