In this episode, we discuss reaction profiles and chemical bonds.

Chemical reactions involve the breaking and forming of bonds, with energy changes occurring in the process. 

Bond breaking requires energy input and is thus endothermic, while bond formation releases energy and is exothermic. 

The overall energy change of a reaction can be determined by comparing the total energy required to break bonds in the reactants to the total energy released by forming bonds in the products. 

If more energy is released than consumed, the reaction is exothermic and has a negative energy change. Conversely, if more energy is needed to break bonds than is released by forming them, the reaction is endothermic and has a positive energy change. 

Calculating this energy difference using bond energies allows us to predict whether a reaction will release or absorb heat.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we will discuss reaction profiles requirements.

Successful chemical reactions necessitate collisions between the involved particles.

Furthermore, these collisions must occur with a minimum amount of energy, known as the activation energy.

Without both physical contact and sufficient kinetic energy during these encounters, a reaction will not proceed effectively.

Therefore, both collision and adequate energy are fundamental prerequisites for a chemical transformation to happen.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we discuss energy conservation.

Chemical reactions involve the transfer and conservation of energy, meaning energy is neither created nor lost. 

Exothermic reactions release energy into their surroundings, often causing a temperature increase, with examples like combustion and neutralization.

Conversely, endothermic reactions absorb energy from their surroundings, leading to a decrease in temperature, as seen in thermal decomposition and the reaction between citric acid and sodium bicarbonate.

Therefore, energy exchange is a fundamental aspect of all chemical transformations.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we will discuss the electrolysis of aqueous solutions and half equations.

Predicting products during the electrolysis of aqueous solutions is complex due to water's dissociation into hydrogen and hydroxide ions. 

At the positive electrode (anode), either halogens form if halide ions are present, or oxygen gas is produced otherwise. 

Conversely, at the negative electrode (cathode), hydrogen gas evolves if the metal is more reactive than hydrogen, while the metal itself deposits if it's less reactive. 

These electrode reactions can be represented by half-equations, illustrating the oxidation (loss of electrons) at the anode and reduction (gain of electrons) at the cathode, as exemplified by the electrolysis of lead bromide.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we discuss using electrolysis to extract reactive metals.

Electrolysis is a method employed to extract reactive metals, such as aluminium, from their molten ores because these metals are more reactive than carbon. 

This process involves passing an electric current through the molten compound, causing the metal ions to be reduced at the cathode, forming the pure metal. 

At the anode, oxygen typically forms and reacts with the carbon electrode, producing carbon dioxide. 

While effective for obtaining highly reactive metals, electrolysis is a costly procedure due to the substantial energy required to melt the ore and generate the necessary electrical current. 

Therefore, although crucial for specific metal extractions, the energy demands represent a significant drawback of this technique.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we cover strong and weak acids.

This source clarifies the fundamental difference between strong and weak acids in aqueous solutions. 

It emphasises that acid strength is defined by the degree of ionisation, not concentration. 

Strong acids undergo complete ionisation, releasing all their hydrogen ions, while weak acids only partially ionise, resulting in fewer hydrogen ions in solution. 

Examples of common strong acids like hydrochloric, sulfuric, and nitric acid are provided, alongside ethanoic acid as a typical weak acid. 

It should be noted that the majority of acids are classified as weak.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we talk about measuring pH.

Determining the acidity or alkalinity of a substance, known as measuring pH, can be achieved through different methods. 

One approach involves using a universal indicator, which displays a spectrum of colours that correlate to specific pH values. Alternatively, a pH probe provides a direct numerical reading of the pH level.

Furthermore, natural substances like red cabbage contain compounds such as anthocyanin that behave similarly to litmus paper, changing colour in response to acidic or alkaline environments, thus offering another means of pH indication.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we look at the practical procedure for isolating a pure, dry-soluble salt. 

The process begins with reacting an acid with an insoluble solid, such as an oxide or carbonate. 

Next, filtration is employed to eliminate any unreacted solid material. The resulting solution, containing the dissolved salt, then undergoes crystallisation, involving gentle heating in a water bath to evaporate water and promote crystal formation. 

Finally, cooling allows for further crystallisation, yielding the desired pure, dry salt sample.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we discuss soluble salts, which are compounds capable of dissolving in water.

The provided text outlines a method for their creation, specifically through the chemical reaction between acids and insoluble solid substances like metal oxides.

An example illustrates this process, showing how copper oxide reacts with sulfuric acid to yield the soluble salt copper sulfate and water.

This reaction demonstrates a practical approach to synthesising soluble salts in a laboratory setting.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!

In this episode, we discuss the neutralisation of acids.

Neutralisation reactions involving acids are explored in this source, which explains how acids react with different types of bases.

Specifically, it outlines the reactions of acids with metal carbonates, metal oxides, and metal hydroxides.

For each base type, a general equation is provided alongside a concrete example using hydrochloric acid.

These reactions consistently result in the formation of salt and water, with the reaction involving metal carbonates also producing carbon dioxide.

Don't miss out on subscribing for more educational content tailored to help you succeed in your exams. Perfect for AQA, OCR, Edexcel, CIE and WJEC exam boards.

⁠Click here to see all of our GCSE Chemistry content!