Law of conservation of mass

Definition

The law of conservation of mass states that mass cannot be created or destroyed in a chemical reaction; it can only change forms. This principle is fundamental in understanding chemical reactions, as it emphasizes that the total mass of reactants must equal the total mass of products, ensuring that all atoms present at the start are accounted for at the end.

5 Must Know Facts For Your Next Test

1. In any closed system, the total mass remains constant during a chemical reaction, regardless of the processes occurring.
2. The law of conservation of mass is critical for balancing chemical equations, as it ensures that each element's quantity is preserved before and after the reaction.
3. During oxidation-reduction reactions, mass conservation is observed by tracking the transfer of electrons and ensuring that all atoms are present in the final products.
4. Mass spectrometry can be used to experimentally verify the law of conservation of mass by measuring the mass of reactants and products in a reaction.
5. This law laid the groundwork for modern chemistry and is crucial for various applications, including biochemical pathways and industrial processes.

Review Questions

• How does the law of conservation of mass apply to balancing chemical equations?
  • The law of conservation of mass requires that when balancing chemical equations, the number of atoms for each element must be equal on both sides of the equation. This means that you cannot create or destroy atoms; you can only rearrange them. When you adjust coefficients in a balanced equation, you ensure that the total mass remains constant, reflecting that the sum of reactants equals the sum of products.
• Discuss how oxidation-reduction reactions exemplify the law of conservation of mass.
  • In oxidation-reduction reactions, the law of conservation of mass is evident as both oxidation and reduction involve electron transfer between substances while maintaining total mass. The number of atoms involved before and after these reactions remains unchanged, demonstrating that while electrons may shift locations between atoms, no atoms are lost or gained. This reinforces that total mass is conserved throughout the reaction process.
• Evaluate how the law of conservation of mass influences modern scientific practices in fields such as bioengineering.
  • The law of conservation of mass plays a vital role in bioengineering by guiding experimental design and analysis in biochemical reactions and metabolic pathways. It ensures accurate calculations regarding reactants and products during enzyme-catalyzed reactions or cellular processes. By applying this principle, bioengineers can develop efficient bioprocesses and predict outcomes in drug formulation and synthetic biology while maintaining sustainable practices.

Related terms

Chemical Reaction: A process in which substances, known as reactants, undergo a transformation to form new substances called products.

Stoichiometry:

The calculation of reactants and products in chemical reactions, which is based on the law of conservation of mass.

Oxidation: A chemical process involving the loss of electrons or an increase in oxidation state, often occurring alongside reduction reactions.