How many atoms of titanium are there in 0.125 mole of each of the following? a. ilmenite, FeTiO3

How many atoms of titanium are there in 0.125 mole of each...

Key Concepts

Stoichiometry

Stoichiometry is the branch of chemistry that relates the quantities of reactants and products in chemical reactions, based on the ratios implied by their balanced chemical equations and formulas. It provides a framework for quantitative calculations involving moles, masses, and numbers of particles.

Mole Concept

The mole is a fundamental chemical unit used to express amounts of a chemical substance. One mole contains exactly 6.022 x 10^23 entities (Avogadro's number), allowing scientists to translate between microscopic particles and macroscopic quantities of material.

Avogadro's Number

Avogadro's number, approximately 6.022 x 10^23, is the number of particles found in one mole of a substance. It is essential for converting moles of a substance to the actual number of atoms, molecules, or formula units in chemical calculations.

Chemical Formula Interpretation

Interpreting a chemical formula involves determining the number and types of atoms present in a compound. This skill is crucial for calculating how many atoms of a particular element are contained in one formula unit of a compound and thereby in any given amount of that substance.

Transcript

00:01 All right, this problem is going to just really be asking us to do mole conversions.

00:06 And we have to come up with some of these conversion factors.

00:10 So they're a little bit different than some of the easier dimensional analysis you probably did at the beginning of the year.

00:17 We have 0 .125 moles of f -e -t -i -o -3.

00:26 I want to know how many moles and then atoms this has of titanium.

00:34 Okay.

00:35 So that's what we have to figure out how to get to.

00:38 In order to do that, you can very simply look at the compounds in one mole of f .e.

00:49 Ti -o -3.

00:52 How many titaniums are there? there's no subscript next to the t -i in the compound, which means i only have one.

01:03 Okay.

01:04 That gets me to moles of titanium.

01:07 I can cancel out moles of feti .03, i'm currently in moles of titanium, right? in order to get from moles into atoms, i can then take that and do 6 .022 times 10 to the 23rd.

01:23 This is atoms of titanium, and we're going to put it over one mole.

01:30 Remember, this is avagadro's number.

01:32 Avogadro's number by definition is 6 .022 times 10 to the 23rd of whatever you happen to be left.

01:40 At, whether it's atoms, molecules, cupcakes, whatever.

01:47 This allows me to cancel out my moles of titanium, and i'm left with atoms of titanium.

01:54 Now, i understand writing out all of this work is tedious, but it is something that i highly recommend that you do so that you can follow your units, and it will help you in the long run.

02:06 When we solve this, 0 .125 times avagadro's number of 6 .022 times 10 to the 23rd.

02:12 I get 7 .53 times 10 to the 22 atoms of titanium.

02:22 The second compound that they want us to use is titanium for chloride.

02:30 So this requires you to remember a little bit of naming.

02:33 When you see a compound that has those roman numerals, it means that there is a 4 plus charge, right? ivy is 4 in roman numerals.

02:41 All of these are cat ions.

02:44 Or positive ions.

02:46 So that four in roman numerals means that the titanium has a four plus charge.

02:52 Chloride came from chlorine.

02:55 That is in group 7a.

02:56 Hopefully you remember that that is a minus one charge.

03:00 So if i'm crossing these charges, this is really a one, a negative one charge for the chlorine.