Final answer:
Scientists use the International System of Units (SI Units), part of the metric system, for measuring physical properties. It includes base units like meters, kilograms, and seconds, and allows for clear, standardized communication in science. The United States National Institute of Standards and Technology (NIST) supports these standardized units for international consistency.
Step-by-step explanation:
Most scientists use the International System of Units (SI Units), also known as the metric system, to measure physical properties of elements. This system includes base units such as the meter for length, the kilogram for mass, and the second for time. Additional units like the liter for volume and degrees Celsius for temperature are derived from these base units. The SI Units are universally accepted in the scientific community due to their ease of use and standardization, where each unit increases by a factor of ten.
Units are extremely important in expressing measurements because they provide a standard that everyone agrees to use as a reference. For example, stating that a distance is "5 kilometers" conveys a clear and specific amount, where '5' is the number of units and 'kilometers' is the scale of measurement.
For accurate scientific communication, a number must always be accompanied by an appropriate unit to convey the quantity being measured, thus avoiding any ambiguity. This system is adopted worldwide and supported by the United States National Institute of Standards and Technology (NIST).