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The type of REACTION in which substances GIVE simple PRODUCT is called Direct COMBINATION of Synthesis

Answer:

YES popping of POPCORN is a physical change and BOILING of egg is a CHEMICAL change.

EXPLANATION:

Popping of popcorn is physical change because the appearance of the kernel changes but not its chemical properties or substance.

Boiling of egg is a chemical change because on boiling the chemical nature of protein present in egg changes which is irreversible.

EXPLANATION:

CITRIC ACID is the EXAMPLE...............

more common states are +2 and +4

it belongs NICKEL group

ANSWER:

IUPAC NAME is

N-methyl ETHANAMIDE

ANSWER:

it will be FOUND in GROUP 8

Explanation:

. Law of conservation of MASS :This law was stated by Lavoisier in 1744. It states that “In all physical and chemical changes, the total mass of reactants is equal to total mass of products.”

2. Law of constant proportions (or constant com-position) : This law was first stated by Proust in 1797. According to the law “a chemical compound is always found to be made up of the same elements combined together in the same proportions by weight” e.g. the ratio of hydrogen and oxygen in pure WATER is always 1: 8 by weight. This law is also called law of definite proportions.

Dalton’s Atomic theory : Postulates of Dalton Atomic Theory

Matter is made up of extremely small indivisible particles called atoms.

Atoms of the same substance are identical in all respects i.e., they possess same size, shape, mass, chemical properties etc. Atoms of different substances are different in all respects i.e., they possess different size, shape, mass etc.

Atom is the smallest particle that takes part in a chemical reaction.

Atoms of different elements May combine with each other in a fixed simple, whole number ratio to form compound atoms.

Atoms can neither be created nor destroyed i.e., atoms are indestructible.

4. Atom : It is the smallest particle of an element which can take part in a chemical change. It may or may not be capable of independent existence.

5. Symbol: The abbreviation used for lengthy names of elements are termed as their symbols.

The symbol of an element is the first letter or the first and another letter of English name or Latin name of the element. While writing a symbol, the first letter is always capital and the second is always small.

6. Molecule : It is the smallest particle of an element or compound that is capable of inde-pendent existence and shows all the properties of that substance.

[The molecules of an element is made up of only one and same type of atoms, while the molecule of a compound is made up of dissimilar atoms]

7. Atomicity : The number of atoms present in a molecule of an element or a compound is KNOWN as its atomicity. e.g. the atomicity of oxygen is 2 while atomicity ozone is 3.

8. Ion : It is an ELECTRICALLY charged atom or group of atom. It is formed by the loss or gain of electrons by an atom. Ions are of two types :

(i) Cation : It is positively charged ion and is formed by the loss of electron from an atom e.g. H+, Na+, Ca2+, Al3+, NH4+ etc.

(II) Anion : It is negatively charged ion and is formed by the gain of electrons by an atom, e.g. Cl–, O2-, C–, F–, CO32- PO43- etc.

9. Valency : The combining power (or capacity) of an element is known as its valency.

10. Formula of simple and molecular compounds Binary compounds are those compounds which are made up of two different elements e.g. NaCl, KBr, CaO etc. Following rules are to be followed for writing the formula.

(i) The valencies or charges on the ions must be balanced.

(ii) For a compound made up of a metal and a non-metal, the symbol of metal is written first.

(iii) In compounds formed with polyatomic ions, the ion is enclosed in a bracket before writing the number to indicate the ratio.

11. Atomic mass of an element : The atomic mass of an element is the numerical number which indicates how many times an atom of an element is heavier than 1/12 of mass of an atom 12 of carbon-12. For example, the atomic mass of magnesium (Mg) is 24 which indicates that one atom of magnesium is 24 times heavier than 1/12 of a carbon-12 atom.

12. Gram atomic mass : The atomic mass of an element expressed in grams is known as gram atomic mass. (Gram atomic mass is also known as gram atomic weight)

13. Molecular mass : The number of times a molecule of a compound is heavier than the 1/12 of the mass of C-12 atom, is known as its molecular mass.

The molecular mass is equal to the sum of the atomic masses of all atoms present in one molecule of the substance. For example H2 contains two atoms of hydrogen, so molecular mass of H2 is 2 (2 x 1 =2)

14. Formula unit mass : It is equal to the sum o atomic masses of all the atoms in a formul unit.

.

ANSWER:

ffggghhgggjj

Explanation:

bbhhgggggggggggggggghhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhygyyhhyyhhyyyyu7yyyyuyyy6yyy6yyyyy6yyyyyhhhhhhgggggggggggggggggggggggggggghgjgggghhhhhhhhhhhh

huj

ANSWER:

The main postulates of VSEPR theory are....

• The shape of molecule depends on the number of valence shell electron pair around Central atom.
• The pair of electron in the valence shell repel each other since then their electron clouds are NEGATIVELY charged.
• These pair of electron are tend to occupy such position in SPACE so that there will be minimum REPULSION and thus maximum distance between them makes the molecule more stable.
• A multiple bond is treated as single electron pair.

ANSWER:

• CaCO3+HNO3---->CA(NO3)2+CO2+H2O

ANSWER:

Compressibility is a property of matter to compress means to change its SHAPE for a short TIME by any EXTERNAL FORCE

Answer:

particles - protons, neutrons, and electrons. But, all ATOMS are not the same. You KNOW that the number of protons in an atom determines what element you have. For instance HYDROGEN has one proton, carbon has six. The difference in the number of protons and neutrons in atoms account for many of the different properties of elements. But most of the "real world" physical properties of materials - at least the ones we experience and relate to most - are caused by the electrons. The number and arrangement of electrons in an atom define the chemical characteristics of elements. One way to think of electrons is that they are the part of the atom that "shows". They are the outer coating. They are the glue that holds atoms TOGETHER in chemical bonds. The basic electron number is determined by the number of protons. In a STABLE carbon-12 atom there are six electrons, since there are six protons. But it gets a whole lot more interesting than just counting electrons.

The gas cylinders are transported easily because there are many transport facilities for transporting it some facilities like a TEMPO, TRUCKS, etc

Gas cylinders are easily fitted into these and are SAFELY REACHED to the transported to the destination

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Answer:

Dalton's ATOMIC Theory. 1) All matter is MADE of atoms. Atoms are indivisible and indestructible. 2) All atoms of a given element are identical in MASS and properties. 3) Compounds are formed by a combination of two or more different kinds of atoms.

2 METHYL PROPANE is there CORRECT NAME

Answer:

ionic BONDS are very strong a lot of energy is needed to break them this is why they have HIGH melting and boiling POINT.

ANSWER:

EXPLANATION:

KINDLY SEE the PICTURE

Answer: It will be a straight line.

Explanation: When an OBJECT is in free FALL (as in this CASE) there is uniform acceleration

MATTER is made up of very TINY particles called atom while molecule is the SMALLEST particle of matter which can exist independently and can retain the physical and CHEMICAL PROPERTY of matter

Explanation:

IRON - Fe

steam - H20 in gas form

so,

Fe+H20(G) gives Fe203 +H2

ANSWER:

It is a MICELLE............

Answer:

EXPLANATION:

The wave function psi by itself have no physical Significance. It shows the amplitude of ELECTRON wave ( wave function). However its square that is measures the probability of finding electron of giving energy from place to place in a giving region AROUND the nucleus. The probability of any point MUST be a REAL quantity. It is possible to identify region of space around the nucleus where, there is a high probability of finding electron associated with a certain energy. This space is an atomic orbital.

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ANSWER:

The compressed natural gas or CNG was made by COMPRESSING natural gas under standard atmospheric pressure. This CNG is distributed in cylindrical tank. It is used as a fuel in automobile industries and household processes. It is also used in vehicles as a fuel.

Apart from LNG (liquefied natural gas), CNG is in gaseous form inside the cylinder but the LNG is in liquid form inside the cylinder. When LNG comes out from the cylinder it is in gaseous form but CNG is in gaseous form when it is inside and outside the cylinder. CNG is less expensive than LNG but the mass of gas inside the CNG cylinder is LESSER than LNG.

And the question here is what happens between the molecules of CNG when the cylinder of CNG is slowly used. When the cylinder of CNG is slowly used up, the DISTANCE between the molecules of CNG will increase. The molecules of CNG will move apart from each other and fill the cylinder. We know that CNG is filled in the cylinder as compressed natural gas inside the cylinder, when it is slowly used up there will be space increasing between the CNG molecules to move somewhat freely than before inside the cylinder as it is present in gaseous form. Gaseous molecules tend to move freely when they get more space. So when some of the gaseous molecules goes out then the other molecules get free space and they move freely inside it.

ANSWER:

YES ACID and BASE FORMED

ANSWER:

STAINLESS steel

Explanation:

ANSWER:

The important characteristics of PARTICLES of matter are the FOLLOWING: The particles of matter are very, very small. The particles of matter have SPACE between them. The particles of matter are constantly moving.

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Answer:

Physical properties of materials and systemscan often be categorized as being either intensive or extensive, according to how the PROPERTY changes when the size (or extent) of the system changes. According to IUPAC, an intensive quantity is one whose magnitude is independent of the size of the system[1]whereas an extensive quantity is one whose magnitude is additive for subsystems.[2] This reflects the corresponding mathematical IDEAS of mean and measure, respectively.

An intensive property is a bulk property, meaning that it is a local physical property of a system that does not depend on the system size or the amount of MATERIAL in the system. Examples of intensive properties include temperature, T; refractive INDEX, n; density, ρ; and hardness of an object, η.

By contrast, an extensive property is additive for subsystems.[3]

These two categories are not exhaustive, since some physical properties are neitherintensive nor extensive.[4] For example, the electrical impedance of two subsystems is additive when — and only when — they are combined in series; whilst if they are combined in parallel, the resulting impedance is less than that of either SUBSYSTEM.

ANSWER:

hdehwidkfkjajwn2(3(_8WJRIRIEJSJEBRIDFJRHWJEIFOOREHWJIWJDJWBjejfjskwjAjrjjfjwjdhDJDICIDHWBFEJIWIRGXI;;3+_((#(£;_

ANSWER:

EXPLANATION:

CONSTANT pressure

constant TEMPERATURE

Answer:

i DONT know plz EXPLAIN QUESTION

Answer:

Mn+7

Explanation:

in cations as the positive CHARGE increase means the no. of PROTONS increases and hence the effective NUCLEAR charge increases and attraction increases and atomic radius DECREASES

Answer:

+3 OXIDATION NUMBER is SEEN in Cr+3

Hope this will HELP uh!!

Answer:

The kilogram (abbreviation, KG) is the SI unit of mass.

The International System of Units (abbreviated SI from SYSTEME internationale , the French version of the name) is a scientific METHOD of expressing the magnitudes or quantities of important natural phenomena. There are SEVEN BASE units in the system, from which other units are derived.

Answer:

here t SYMBOLIZES one fouth of a first order reaction

Explanation:

t=2.303 ×㏒[R.]

     K                [R.]/4

t=2.303 ×㏒4[R.]

    K               [R.]

t=2.303×2㏒2

     K

t=2.303×(2×0.30103)

      K

t=2×0.693  

         k

t=2×HALF LIFE of a first order reaction [half life of a 1st order reaction =0.693

                                                                                                                   K]

so,t=2×15min

      =30min

      =1800s

,

Explanation:

FERROUS Ammonium SULPHATE, FeSO4(NH4)2SO4.6H20

pottash Alum K2SO4.Al2(SO4)3.24H2O

and other ALUMS

Answer:

Performing the calculations to round it off to nearest three digits….

Explanation:

It is 3.26104 X 1.54106…

It is a simple multiplication as FAR as I can see……as both digits are in BRACKETS,

So the correct answer when you multiply we get . 5.025458024

Now when we want to round it off to three digits, we get 5.025.

So the correct answer is 5.025.

You have to keep in mind that as the answer has to be rounded off to three DECIMAL places, so you have to focus on digits in the answer that is in decimals places…..0254580…

Now focusing on only three digits…..025 and the next digit is “4” , which is less than “5”. So it has to be rounded off to nearest zeros.

Thus we get the answer 025. And the correct answer is 5.025.  

Answer:

yes

Explanation:

yes yes firecracker SUDDENLY BLAST and HEAT is RELEASED the fire crackers are an example of spontaneous combustion

ANSWER:SODIUM BISULFITE (or sodium bisulphite, sodium hydrogen SULFITE) is

NAHSO3.

t= 0.693÷k

K=0.693÷1600

K= 4.3 ×10^-4

2t1/2=T

T= 2×1600

T= 3200years

I HOPE that this is the answer.

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Answer:

1 mol Ca(NO3)2 = (40.078 G + 28.0134 g + 95.9964 g) = 164.088 g

Explanation:

when finding the formula mass of a compound, multiply the NUMBER of MOLES to the mass of the SUBSTANCE of each atom in the compound. Then add the products to find the atomic mass.

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Explanation:

Cr2O7 (2-) + C2O4(2-) ----> Cr(3+) + CO2

In reactant SIDE OXD number of : Cr in Cr2O7(2-) =+6 and C in C2O4(2-) = +3

In product side oxd number of Cr in Cr(3+) = +3 and C in CO2 = +4

Now,

C2O4(2-) -----> 2CO2 + 2e- ....... ( Eq 1)

Cr2O7(2-) + 14H+ + 6e- -----> 2Cr(3+) + 7H2O..... (Eq2)

(total charge in reactant side is +12 and in product side is +6)

{We add e- in the side where charge is more..... This means we will add 6e- in reactant side}

Now.... To balance charge in( eq 1)....multiply( eq 1) by 3

==> 3C2O4(2-) -----> 6CO2 + 6e- ...... (Eq 3)

From 2 and 3

3C2O4(2-) + Cr2O7(2-) + 14H+ ---> 6CO2 + 2Cr(3+)

+7H2O

The charge ie 6e- gets cancelled becoz one is on the reactant side and other is on product side

I hope it helps you☺️

EXPLANATION:

apka EQUATION galat h

H2O nahi HOGA H2 hoga

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Steps:

1. Select the longest chain

2. No from that side from where there will be less no. Given to substituents

Then name accordingly.

Identification of IUPAC is lies in its name

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Answer:2%

Explanation:

0.5/25x100= 2%

ANSWER:

In SCIENCE, we have a NAME for this, called Avogadro's number, and it describes the number of representative particles in one mole of a substance. The INVERSE mole UNIT tells us there are 6.022×1023 particles of something *per mole*

Answer:

With CONCENTRATED nitric ACID, more nitro groups substitute around the ring to give 2,4,6-trinitrophenol (common name: PICRIC acid).

ANSWER:

it COULD be that there is CONVERTER

Sorry it's a incomplete question

But i can tell you the VALUE of temperature at which CELSIUS and Fahrenheit will have same value

It is -40°C ( temperature)

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EXPLANATION:

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During prophase of meiosis I, the double-chromatid homologous pairs of CHROMOSOMES cross over with each other and often exchange chromosome SEGMENTS. This recombination creates genetic diversity by allowing genes from each parent to intermix, resulting in chromosomes with a different genetic complement.

The three main sources of genetic VARIATION arising from sexual reproduction are: Crossing over (in prophase I) Random assortment of chromosomes (in metaphase I) Random fusion of gametes from different parents