Mass by volume percentage

• Mass by volume percentage can be defined as the mass of solute dissolved in 100 mL of the solution.
• For instance, mass by volume percent of a solution with 1 g of solute dissolved in 100 mL of solution will be 1% or 1% (mass/volume).
• Mathematically, Mass by volume% =

Dated: - /- / - (enter date here)

Dear diary,

Not a single day goes by when I do not feel ridiculed by my fellow classmates. I do not understand that what is my fault in all of this. I wear a blue faded dress to class and therefore everybody laughs at me. Nobody cares about how I feel or how I feel ashamed of myself. I am embarrassed about my attire but there isn't much that I can control in life. In order to get rid of this I ended up lying that I have one hundred dresses at home. But now since everybody knows that I  cannot prove this, I have decided not to go to school anymore.

I have to go now.

Goodbye.

Wanda Petronski

The reactant which reacts completely in the reaction is called limiting reactant or limiting reagent.

The reactant which is not consumed completely in the reaction is called excess reactant .

Aristotle is known as the “Father of Biology” because he extensively studied the natural world and contemplated its origins using scientific insights and systematic observations rather than attributing it to divine intervention. He was also the first to uncover the relationship between animals and establish a system of classification. 

During his time, Aristotle made many observations about the local flora and fauna, for instance, he was the first to document that an octopus can change its colour when disturbed. He also named close to 500 species of animals, identifying their characteristic features and documenting them.

A n s w e r:
2) option is correct.

y = 2, means point is represted on y-axis.

If we draw a line through it then it will parallel to the x-axis.

CH₄ + 2O₂ -> CO₂ + 2H₂O

GRAM MOLECULAR MASS OF CO₂ = 12 +2(16) = 44g

From the reaction it is clear that 1 mole of methane on complete combustion produces 44g (1 mole) of carbon dioxide.

therefore moles of CH₄ required to produce 22g of CO₂ are:

(22) * (1/44) = 1/2 moles

लेखक उस स्त्री के रोने का कारण इसलिए नहीं जान पाया क्योंकि उसकी पोशाक रूकावट बन गई। जब उसने उस खरबूज़े बेचने वाली स्त्री को घुटनों पर सिर रखकर रोते देखा और बाजार में खड़े लोगों का उस स्त्री के संबंध में बातें करते देखा तो लेखक का मन दुखी हो उठा। कारण जानना चाहते हुए भी वह ऐसा नहीं कर पाया। यद्यपि व्यक्ति का मन दूसरों के दुःख में दुःखी होता है परन्तु पोशाक परिस्थितिवश उसे झुकने नहीं देती।

• The word ‘stoichiometry’ is derived from two Greek words - stoicheion (meaning element) and metron (meaning measure).
• Stoichiometry deals with the calculation of masses (sometimes volumes also) of the reactants and the products involved in a chemical reaction.
• This is done using balance chemical equation.

This method is also called trial and error method, or inspection method. In this method, coefficient before the formulae or symbols of the reactants and products are adjusted in such a way that the total number of atoms of each element only both the sides become equal. This is called material balance, or mass balance. In this method first of all, atoms of the element which appears least in the chemical equation should be balanced. Then, the next one, and so only.

A chemical equation has its own limitations. They do not provide information about: 

1. The physical state of reactants and products Hence, the symbols ‘s’ for solid, ‘l’ for liquid, ‘g’ for gas and ‘vap’ for vapour are added. 
2. Conditions such as temperature, pressure and catalyst affecting the reaction 
3. Concentration of reactants and products Hence, in some cases, for dilute ‘dil.’ and for concentrated ‘conc.’ are added. 
4. The nature of the chemical reaction; whether it is reversible or irreversible reaction. 
5. Speed of the reaction 
6. Heat changes accompanying the reaction; whether heat is given out or absorbed 
7. Time taken for completion of the reaction A reaction may or may not be complete, and the equation does not reveal it.

The atomic mass of metal M is 56. Calculate the empirical formula of its oxide containing 70% of M.

(i) To calculate the percentage of oxygen.



(ii) To calculate the empirical formula of oxide:

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Phishing is a scam where an attacker uses fake or partial information to try to trick someone into revealing passwords and other confidential information, typically via email or social media. LastPass helps protect you against fake-website phishing attacks by not filling your credentials when it does not see a URL or field match.

Viruses are programs that infect software on your computer. When you run this software, it causes the virus to spread throughout your computer. Basically, the virus can replicate itself and continue spreading to other computers (much like a biological virus), causing hardware and software issues.

Worms are programs that replicate and spread through a network, infecting multiple devices. Unlike a virus, a worm does not need to attach itself to an existing software. Worms cause harm to a network, while viruses cause harm to a targeted computer.

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Molecular mass of {tex}KHSO_(4)=39+1=32+64=136.0u{/tex}

Percentage of potassium =(39u) / (136u)×100 = 28.68%
Percentage of hydrogen =(1u) / (136u)×100 = 0.735%
Percentage of sulphur =(32u) / (136u)×100 = 23.53%

Percentage of oxygen =(64u) / (136u)×100 = 47.06%

S o l u t i o n:
The chemical formula of FeSo4 . 7 H2O
= 55.8 + 32.1 + 16x4 + 7x18
= 277.9

The percentage of water of crystallization=
= (7 x 18) / 277.9 x 100 %
= 45.34 %

Pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a P-O-P linkage. A number of pyrophosphate salts exist, such as Na₂H₂P₂O₇. Often pyrophosphates are called diphosphates. The parent pyrophosphates are derived from partial or complete neutralization of pyrophosphoric acid.