Browse Definitions :
Definition

amount of substance (material quantity)

Amount of substance, also called material quantity, is a dimensionless expression of the number of particles in a sample. The particles are usually atom s, but they can be protons, neutrons, electron s, or more fundamental particles such as quarks. Amount of substance can also be expressed in terms of composite particles such as molecules.

The standard unit of material quantity in the International System ( SI ) is the mole . This unit is based on the mass of 0.012 kilogram (kg), or 12 grams (g), of carbon 12 (C-12), the nucleus of which contains six protons and six neutrons. One mole is equal to approximately 6.022169 x 10 23 , and is also called the Avogadro constant.

Also see atom , mass , mole , and International System of Units ( SI ).

This was last updated in January 2011
SearchCompliance
  • OPSEC (operations security)

    OPSEC (operations security) is a security and risk management process and strategy that classifies information, then determines ...

  • smart contract

    A smart contract is a decentralized application that executes business logic in response to events.

  • compliance risk

    Compliance risk is an organization's potential exposure to legal penalties, financial forfeiture and material loss, resulting ...

SearchSecurity
  • threat modeling

    Threat modeling is a procedure for optimizing application, system or business process security by identifying objectives and ...

  • social engineering

    Social engineering is an attack vector that relies heavily on human interaction and often involves manipulating people into ...

  • distributed denial-of-service (DDoS) attack

    A distributed denial-of-service (DDoS) attack is one in which multiple compromised computer systems attack a target, such as a ...

SearchHealthIT
SearchDisasterRecovery
  • change control

    Change control is a systematic approach to managing all changes made to a product or system.

  • disaster recovery (DR)

    Disaster recovery (DR) is an organization's ability to respond to and recover from an event that affects business operations.

  • risk mitigation

    Risk mitigation is a strategy to prepare for and lessen the effects of threats faced by a business.

SearchStorage
  • race condition

    A race condition is an undesirable situation that occurs when a device or system attempts to perform two or more operations at ...

  • storage security

    Storage security is the group of parameters and settings that make storage resources available to authorized users and trusted ...

  • cloud storage

    Cloud storage is a service model in which data is transmitted and stored on remote storage systems, where it is maintained, ...

Close