Measurements in Chemistry Flashcards
Define: Matter
Anything that has mass and takes up space
Define: Unit
A quantity that describes (and defines) the measurement being made
Define: Significant Figure
A digit in a measurement that contributes to the measurement’s precision
Define: Weight
A measure of how strongly gravity pulls on an object
Define: Mass
A measure of how much matter exists in an object
Define: Density
A measure of how tightly packed the matter in a substance is
How is the metric system different from the English/Standard system of measurement?
The metric system uses base units, for which all other units of measurement are defined relative to them.
To measure mass: base unit grams. To measure distance: meters. To measure volume: Liters.
All measurements within the metric system have a certain value that is defined by how much larger or smaller it is than it’s base unit.
What are significant figures?
A digit in a measurement that contributes to it’s precision.
What is Mathematical Importance?
The accuracy an amount/ measurement is; how close to “correct” it is.
What is Scientific Significance?
The precision to which an amount/measurement is measured; tells you to what scale the scientist measured.
What makes Scientific Significance different from Mathematical Importance?
Scientific Significance has more to do with how “closely” you look at a measurement, for example how closely a ruler measures an object. Unlike Mathematical Importance, which is more concerned with “correct” answers. Mathematical Importance talkes about accuracy (whether or not the measurement is actually the right number), and Scientific Significance talks about the precision of the measuring instrument.
Relationship between density, mass, and volume.
Density= mass/volume
Fun fact: most substances have their own unique density!
Use Algebra to make a new relationship from the density, mass, and volume relationship.
Volume=mass/density
Define: Volume
A derived unit that measures how much space a substance takes up
(this is exclusive to substances within a defined, enclosed space. So, fun fact: a cup without a lid TECHNICALLY has no volume.)
The three criterion for a significant figure.
- All non-zero figures are significant.
- A zero is significant if it is between two significant figures.
- Zeros are significant if they are at the end of the number and to the right of the decimal point.
