The answer is that you are converting based on number, not on mass. … Big, because atoms and molecules are way too small to count, so we mass large numbers of them instead, and use molar mass to convert to the NUMBER of moles of them.
Why is it important to convert moles to grams?
Balances DO NOT give readings in moles. So the problem is that, in chemistry, we compare amounts of one substance to another using moles. That means we must convert from grams, since this is the information we get from balances.
Why do we need to use moles when we try to determine amounts of reactants and products in a reaction?
We use the mole (mol) to represent the amount of substances in chemistry because the numbers of atoms and molecules in each substance is so large. The value given 6.023 x 1023 is called Avagadro’s number for the scientist that found the number of atoms in 12 grams of carbon 12. Why use 12 grams?
Why do we need to use the mole instead of mass to compare amounts of different substances?
In summary The mole is used extensively in the sciences because we need a unit that describes an amount of substance, which is different from the mass of a substance or how much space a given amount of substance occupies.
Why do chemists convert between moles and grams?
Chemists use the mole because it is a convenient way of knowing how many representative particles are in a sample. … Each one-mole quantity has 6.02 1023 particles (atoms), but they will have different masses. State the conversion factors needed to convert between mass and moles of the element fluorine.
How do u convert grams to moles?
Using a calculator, divide the number of grams by the molar mass. The result is the number of moles in your element or compound. For example, imagine you have 2 g of (NH4)2S and you want to convert it to moles. The molecular mass of (NH4)2S is 68.17g/mol.
What are the 4 types of stoichiometry problems?
4 types of stoichiometry problems
- Mole – mole.
- Mole – mass.
- Mass – mole.
- Mass – mass.
Why use moles and not mass?
Because atoms, molecules, and other particles are all extremely small, you need a lot to even weigh them, so that’s why chemists use the word “mole.” Keep in mind that not everything weighs the same if you have a mole of it. A mole refers to the number of particles you have, not the mass.
Why do we use moles and not just talk in grams?
Why don’t we simply stick with units like grams (and nanograms and kilograms, etc.)? The answer is that moles give us a consistent method to convert between atoms/molecules and grams. It’s simply a convenient unit to use when performing calculations.
What is the relationship between mole Avogadro number and mass?
Avogadro’s number is an absolute number: there are 6.022×1023 elementary entities in 1 mole. This can also be written as 6.022×1023 mol-1. The mass of one mole of a substance is equal to that substance’s molecular weight.
Why don’t they just count each particle?
Why don’t they just count each particle? Chemists prefer using the mole over counting each particle because one particle is way to small to count by it self, but using the mole, 6.02×10^23, lets them measure a lot more accurately and quicker.
What is Mole concept class 9th?
The mole concept is a convenient method of expressing the amount of a substance. Any measurement can be broken down into two parts – the numerical magnitude and the units that the magnitude is expressed in. … It primarily focuses on the unit known as a ‘mole’, which is a count of a very large number of particles.
Why is it important to convert to moles when doing stoichiometry problems?
That is an extremely common question when first using stoichiometry. The answer is that you are converting based on number, not on mass. … Big, because atoms and molecules are way too small to count, so we mass large numbers of them instead, and use molar mass to convert to the NUMBER of moles of them.
What is the role of a mole in stoichiometry calculation?
In general, mole ratios can be used to convert between amounts of any two substances involved in a chemical reaction. To illustrate, let’s walk through an example where we use a mole ratio to convert between amounts of reactants.
How do I calculate moles?
Use the molecular formula to find the molar mass; to obtain the number of moles, divide the mass of compound by the molar mass of the compound expressed in grams.