Heck to the Yes Sister!

remember all those pesky chemical equations and how to balance them out?  let's take a look at how they're used in thermochemistry! hot 1 H₂(g) + ½ O ₂ (g)  →  1 H ₂O(g) + 241.8 kJ this is an example of a "thermochemical equation"! it's a little different from what u might be used to for 2 reasons: what is this "241.8" kJ nonsense!?! that's not any chemical I recognize! there's a fractional term (½)!! what's up with that!?!? addressing the "241.8 kJ":  this is a measure of the enthalpy change  ( ΔH) , or the change in the system's total energy  that happened during the reaction!  remember that chemical reactions always involve the making and breaking of bonds - this requires a change in the system's energy. for our purposes, energy change will always be measured in joules or kilojoules (1000 J = 1 kJ)! the fact that the ΔH is listed on the "products" side of the equation means that th

let's examine exothermic and endothermic reactions* a bit more thoroughly! *for the purpose of thermochemistry, i'll refer to all changes in matter as "reactions" exothermic   - heat energy is released into the surroundings (i.e. "produces heat") the products of exothermic reactions have less potential energy than the reactants examples: freezing - liquid water forming ice at 0 degC     ⇌ energy +   condensation - water vapour turns into water droplets   ⇌ energy +      it might seem a bit unintuitive to think of these reactions as producing "heat" but it makes sense if you think about it! the three states of matter... classic molecules in a liquid have more kinetic ("heat") energy than a solid - they're free to slip and slide around as they please!  liquid molecules - full of energy and a little like a bouncy ball pit! in a solid, they just sit near each other and vibrate solid molecules - not very

oh boy, calorimetry! this is where things become a bit math-y, but i'd say it's not too bad at this point! good luck! u might recognize the word "calorie" in "calorimetry".  we need calories! that's a very smart observation of u! calories r just a measure of energy - the amount of heat used to raise the temperature of a gram of water by one degree Celsius. this "calorie" is different from what u might hear nutrition people talking about though. those weirdos r talking about kilocalories, also written as Calories. 1 Cal = 1000 cal. a little confusing right?  anyway, this concept of using a specific amount of heat to raise a gram of something  1°C  is gonna be pretty important for calorimetry...........  but what IS calorimetry anyway?!?!?!? some pretty high tech stuff! Measuring Energy Changes - Calorimetry i've mentioned bomb calorimeters in the last section, but what exactly are they used for? it's right in th

let’s do some thermochemistry - the study of energy changes that accompany physical/chemical changes in matter! in this post, we will discuss...  changes in matter heat & energy changes types of chemical systems these are just the very basics but it's always good to review! 1. Changes in Matter before we can talk about energy changes, we need to discuss changes in matter. these changes can be classified as: physical  - a change in the arrangement of molecules; does NOT produce any new substances e.g. melting ice, boiling water - it’s still H 2 O, just in different forms! boiling water... yummm chemical  - a change in the arrangement of atoms and their electronic structures; produces new compounds e.g. the combustion of methane - produces carbon dioxide and water burning fossil fuels... controversial nuclear  - a change in the nucleus of an atom; produces new atoms! a star burning in space... wow! e.g. nuclear fusion in stars - two hydrogen