Which of the following are both physical and chemical change?Cooking foodPassing of electric currentBoiling of waterAll of above (2024)

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Which of the following are both physical and chemical change?Cooking foodPassing of electric currentBoiling of waterAll of above? ›

Passing of electric current is a chemical change, whereas, boiling of water is a physical change. However, cooking food is a physical as well as chemical change because the texture of food changes and new products are formed as well.

Answer: Cooking of food, boiling of eggs are examples of both physical and chemical changes. In both cases, the physical appearance of the substances change and new substances are formed. Cooking of food is a chemical process since it involves changes in the chemical composition of food.

A burning candle shows both physical and chemical changes.

Key Takeaways. A chemical change results from a chemical reaction, while a physical change is when matter changes forms but not chemical identity. Examples of chemical changes are burning, cooking, rusting, and rotting. Examples of physical changes are boiling, melting, freezing, and shredding.

Expert-Verified Answer

(i) Cutting of trees is a physical change. (ii) melting of butter in a pan is a physical change. (iii) rusting of almirah is a chemical change. (iv)boiling of water to form steam is a physical.

When water is boiled, it undergoes a physical change, not a chemical change. The molecules of water don't break apart into hydrogen and oxygen. Instead, the bonds between molecules of water break, allowing them to change physically from a liquid to a gas.

The burning of wood is an example of a change that is both chemical and physical. When heated, the moisture in the wood turns to vapour, which is a physical change. Burning wood produces carbon dioxide (among other products) and results in a chemical change.

Some examples of physical change are freezing of water, melting of wax, boiling of water, etc. A few examples of chemical change are digestion of food, burning of coal, rusting, etc. Generally, physical changes do not involve the production of energy.

Gasoline is vaporized and the air in the cylinders is compressed, a physical change, before being ignited and combusting, a chemical change. Digestion is another example of both. Food is physically broken down by chewing and chemically broken down by digestive enzymes in the saliva and acid in the stomach.

It occurs when extremely high heat causes a substance to undergo thermal degradation without oxygen or other oxidants, breaking down into smaller and more volatile molecules. Thermal degradation changes the substance's chemical composition and can lead to caramelization or charring.

What are the chemical changes in food processing? ›

The two major chemical changes which occur during the processing and storage of foods and lead to a deterioration in sensory quality are lipid oxidation and non-enzymatic browning. Chemical reactions are also responsible for changes in the colour and flavour of foods during processing and storage.

Physical Changes

If you freeze fruit juice to make a popsicle, this is a change in state. The juice changes from a liquid to a solid. Ice cream melting on a hot day is also a change in state. The ice cream changes from a solid to a liquid.

Maillard browning is a chemical reaction, often known as the browning reaction, that is accountable for the browning and the aroma of food as it gets cooked. It usually occurs between the building blocks of protein i.e., the amino acids and carbohydrates known as reducing sugar.

Food cooking is a chemical change because vegetables and raw ingredients are converted to delicious food which can not be converted back to orignial ingredients.

During digestion, large food particles are converted into smaller components that are entirely different and can be readily absorbed into the bloodstream. The chemical composition of the substance changes and there is a formation of a new substance. Hence, digestion of food is a chemical change.

Some of these changes are physical—the food changes form, shape, and size—but the molecules that make up the food do not change. Other changes in food are chemical.

The physical properties of the eggs, such as their color, texture, and shape, also change when they are cooked. However, these changes are not chemical changes because the composition of the eggs remains the same. Therefore, The cooking of eggs on a hot stove is an example of a chemical change.

Cooking includes both physical as well as chemical changes. It involves cutting of raw vegetables, boiling milk, making butter out from milk, preparing rice and many other things. Out of these, some of the cooking activities are physical changes while some are chemical changes.

During the process of deep-fat frying, various chemical reactions take place. These reactions include oxidation, hydrolysis, polymerization, and isomerization, leading to the formation of several products.