Scientia, meaning knowledge and skill
Answer:
<span>The mole concept is important in chemistry because, "</span>Atoms and molecules are very small and the mole concept allows us to count atoms and molecules by weighing macroscopic amounts of material".
Explanation:
To understand this question lets take an example of Hydrogen atom. Let suppose you need to react Hydrogen with Oxygen. You need exactly Two Hydrogen atoms and one Oxygen atom to form one water molecule.
The mass of 1 hydrogen atom is 1.76 × 10⁻²⁴ grams. How will you count the Hydrogen atoms??? How can you measure exactly for 1 Million Hydrogen Atoms???
Answer to these questions and Calculations lies in Mole. It is found that 1 Mole of Hydrogen weights exactly 1.008 gram and contains 6.022 × 10²³ atoms. Now, having this reference in hand you can calculate for any number of Hydrogen atoms.
Result:
So the Mole helps us to zoom a microscopic level to a macroscopic level. :)
Answer:
2KBr + MgF₂ –> 2KF + MgBr₂
The coefficients are: 2, 1, 2, 1
Explanation:
KBr + MgF₂ –> KF + MgBr₂
The above equation can be balance as illustrated below:
KBr + MgF₂ –> KF + MgBr₂
There are 2 atoms of F on the left side and 1 atom on the right. It can be balance by writing 2 before KF as shown below:
KBr + MgF₂ –> 2KF + MgBr₂
There 2 atoms of K on the right side and 1 atom on the left side. It can be balance by writing 2 before KBr as shown below:
2KBr + MgF₂ –> 2KF + MgBr₂
Now, the equation is balanced.
The coefficients are: 2, 1, 2, 1
The larger the piece the longer it will take to break down. This is because it has more mass that needs to be broken down.