Chemical Reactions - Video Tutorials & Practice Problems
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concept
Chemical Reactions
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in this video, we're going to begin our lesson on chemical reactions. And so chemical reactions consists of the making and or breaking of chemical bonds, leading to changes in matter. And every single chemical reaction has reacted. And products now reactant are going to be the starting material in a chemical reaction. And so you can think of the reactant as the ingredients for the reaction. And then, of course, the products are going to be the ending material in a reaction. And so let's take a look at our image down below, which notices showing a chemical reaction and on the left hand side, notice that we have these building blocks that are broken apart into smaller individual pieces. They're broken down and on the right, notice that the building blocks are coming together to build a larger, more complex structure. And so the beginning of every chemical reaction is going to start off with reactant and so reactant are going to be once again the starting material and a chemical reaction. And over here on the right hand side, what we have is the ending material, and so the ending material is going to be the products And so every chemical reaction is gonna have reactant and a product. And the reactant is always going to be found at the very beginning of a chemical reaction arrow. And the product is going to be found at the very end of a chemical reaction arrow. And so we'll be able to talk about different types of chemical reactions as we move forward in our course. But for now, this concludes our introduction to chemical reactions as well as the difference between reacting some products and we'll be able to get practice as we move forward through our course. So I'll see you all in our next video.
2
concept
Types of Chemical Reactions
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5m
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in this video, we're going to introduce two different types of chemical reactions, and so chemical reactions are gonna be categorized into two groups based on their energy requirement. And so those two groups are going to be listed down below one and two, and also we have two images down below to show those two different groups of chemical reactions. Now the very first group is going to be ender gone IQ reactions. And so ender gone IQ reactions are going to require an input of energy. And so you can think e n and ender gone IQ reactions is for the e n and entering the reaction. And that's because energy needs to enter the reaction, uh, in order for end organic reactions to occur. And so just like this person here is entering into the room. You can think that ender gone IQ reactions require energy to enter the reaction, and so you can see the little symbol here on his shirt represents energy. And so you could think the person coming into the room represents energy entering the reaction. Now, the second type of reaction that you all should know our ex organic reactions and ex organic reactions are practically the opposite of undergone IQ reactions. So instead of requiring an input of energy, they actually are going to release energy into the environment. And so X organic reactions are going to allow energy to exit the reaction. And so you can think the e X and X organic reaction is for the e X and exit the reaction. And so it's just like this person here is exiting the room through this door right here and so you can see the little energy symbol on his shirt. Eso that he's representing energy and he's exiting the room. So let's take a look at our example down below to better understand the difference between undergone IQ and ex organic reactions. So notice that our image is broken up into two halves on the left hand side. Over here. What we're showing you are, uh, the ender. Gothic reactions and end organic reactions are going to be building up larger and more structured molecules. And so when you take a look at our image down below, notice that it's showing the building blocks the broken down building blocks over here on the left hand side as the reactant the starting material or the ingredients for the reaction. And by the end of the reaction, noticed that those starting materials have been built up into a larger mawr complex structure here that is more organized. And so this would be the product over here. And, uh, there is some building up occurring here in this and organic reaction. And because it's an end organic reaction, you can see that energy has to enter this system. And so you can see the entering person here and the energy coming into the chemical reaction. And so if we take a look at the little graph that we have down below, this little plot notice that it has a Y axis that has potential energy that's increasing from the bottom to the top. And it also has the progress of the reaction on the bottom. And so notice that we start off with the reactant. So over here on the left hand side and the reactant have lower energy here in comparison to the products over here which noticed they have higher energy since there's ah, higher bar, so they have higher energy. And so the reason that the products have higher energy is because energy is entering the system here, it's entering into the product. And so energy is required for end organic reactions and for building up larger molecules. Now, on the right hand side, over here, what we're showing you is the complete opposite. We're showing you xer gone IQ reactions and ex organic reactions are gonna be used to break down substances into their smaller components. And so notice that this time we're starting the reaction with reactant that are larger, more complex and built up, and then notice that by the end of the reaction, the molecules are being broken down into their smaller individual components. And so, in this ex organic reaction notice that energy is actually leaving the system, it is exiting the system. So you can think the e X and X organic is for energy exiting the system. And so when we take a look at the graph down below, notice that the reactant this time have higher energy than the products which are over here on notice. The products over here they have lower energy. And so because the products have lower energy, it means that the energy is exiting the system. It's leaving the system and going into the environment. Energy is being released into the environment, and so energy is going to be released into the environment because there is this difference in energy here, where the reactant air higher and the products are lower energy. And so you can see how an organic and ex organic reactions are practically the opposite of each other. And so the cell can utilize both and organic and ex organic reactions. And we'll be able to talk even Maura about these reactions as we move forward through our course. But for now, this concludes our introduction to end organic and ex organic reactions, and I'll see you all in our next video.
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Problem
Problem
Which of the following statements is true for all exergonic reactions?
a) The products have more total energy than the reactants.
b) The reaction proceeds with a net loss of free energy.
c) The reaction goes only in a forward direction:all reactants will be converted to products.
d) A net input of energy from the surroundings is required for the reactions to proceed.
A
The products have more total energy than the reactants.
B
The reaction proceeds with a net loss of free energy.
C
The reaction goes only in a forward direction:all reactants will be converted to products.
D
A net input of energy from the surroundings is required for the reactions to proceed.
