pls kindly send me the notes of ch percentage composition
class 8
board icse
subject chemistry
Answers
Percentage composition of a compound is a ratio of an amount of each element to the total amount of individual elements in a compound, which is then multiplied with 100.
example: H2O i.e. Water. Water has 2 molecules of hydrogen, and one mole of water is of 18.0152 grams. And one mole of a hydrogen atom is of 1.008 grams. So, 2 hydrogen moles weighs 2.016 grams. Hence, one mole of water has 2.016 grams of hydrogen mole. Therefore, the percentage composition of hydrogen would be 2.016/18.0152 = 11.19%.
What is Percentage Composition?
The percentage composition of any given compound is nothing but the ratio of the amount of each element present in the compound to the total amount of individual elements present in the compound multiplied by 100. Here, we measure the quantity in terms of grams of the elements present in the solution.
The percent composition of any compound is an expression of its composition in terms of all the elements present. The significance of this composition calculation is found in the chemical analysis
Percentage Composition Formula
We can express the percentage composition of a given element using the formula below:
%CE=gE/gT×100
Here, % CE is the percentage composition of the element E. This is the value that we are going to calculate. The numerator on the right side indicates the total amount of element E present in the compound. On the other hand, the denominator is an expression for the total amount of all the elements present in the compound.
We multiply this ratio by 100 to get the percentage form of the composition.
Answer:
Sis iske liye code ata hai
write tex in tx
Just copy and paste
[tx]<!DOCTYPE html>
<html lang="en">
<head>
<title>Bts army bomb</title>
</head>
<body>
<div id="container" class="army-bomb-container">
<div id="handle" class="handle">
<div id="army-bomb" class="army-bomb"/>
</div>
<style>
body {
background: linear-gradient(45deg, #FBCCB7, #EFAAC9, #CCB6D9, #A2C8ED);
width: 100vh;
height: 300px;
}
.army-bomb-container {
position: fixed;
left: 50%;
top: 50%;
transform: translateX(-50%) translateY(-30%);
}
.handle {
position: relative;
height: 200px;
width: 50px;
background-color: black;
z-index: 0;
}
/* top of the army bomb drawn using pseudo elements on the handle (so that it is drawn behind the glowing animation) */
.handle:before {
position: absolute;
left: 132.5%;
top: -30%;
width: 30px;
height: 10px;
background-color: black;
transform: rotate(45deg);
z-index: -1;
content: "";
}
.handle:after {
position: absolute;
left: 168.5%;
top: -31.5%;
width: 3px;
height: 5px;
background-color: red;
transform: rotate(45deg);
z-index: -1;
content: "";
}
.army-bomb {
position: relative;
left: 50%;
transform: translateX(-50%) translateY(-50%);
width: 150px;
height: 150px;
background-color: white;
border-radius: 75px;
animation: light-up 3s infinite ease-in-out;
}
/* BTS logo drawn using pseudo elements of the army bomb */
.army-bomb::before {
position: absolute;
top: 160%;
left: 34%;
border-bottom: 10px solid white;
border-left: 10px solid transparent;
border-right: 10px solid transparent;
height: 0;
width: 15px;
transform: rotate(90deg);
content: "";
}
.army-bomb::after {
position: absolute;
top: 160%;
right: 34%;
border-bottom: 10px solid white;
border-left: 10px solid transparent;
border-right: 10px solid transparent;
height: 0;
width: 15px;
transform: rotate(-90deg);
content: "";
}
/* glowing animation */
@keyframes light-up {
0% { box-shadow: 0px 0px 50px 1px white; }
50% { box-shadow: 0px 0px 50px 30px white; }
100% { box-shadow: 0px 0px 50px 1px white; }
}
</style>
</body>
</html>[/tex]
