Science Vocabulary: Data, Variables, and Matter Concepts Listen as a podcast

Assuming two samples are made of the same material, how does the size of the sample impact its density?

A larger sample will the same density as the smaller sample

Hypothesis

A testable idea, using data and experiments.

Quantitative Data

Deals with numbers, data that can be measured. Ex. Length, height, temperature, time.

Data

Information gathered through observations or measurements, can be put in tables and on graphs.

Question

What does the scientist want to know about; may be based on observations that have been made. _

Procedure

The steps, sequence, and supplies used to complete an experiment.

Observations

What is noticed through the use of senses or instruments

Constants

The factors that are kept the same during an experiment, should only be one variable tested.

Independent variable

Subject of the experiment, what the scientist is testing the "cause", on X axis

Conclusion

To state results using data, to come up with answer.

Control

A specimen that is left alone, used as comparison to experimental subjects.

Predict

To say what will happen in the future

Qualitative Data

Deals with descriptions, data can be observed but not measured. Ex. Colors, textures, smells, appearance

Dependent variable

What is being measured or observed, what changes because of IV, the "effect", on Y axis

estimated digit

The last digit in the measurement

Significant Figures

All non-zero digits 1-9 are significant

PACIFIC RULE

If a decimal point is PRESENT , start counting from the 1st nonzero digit, counting all digits to the right of it, including zeros.

ATLANTIC RULE

If a decimal point is ABSENT start counting from the 1st nonzero digit, counting all digits to the left of it, including zeros.

Multiplication/Division Rule

Round the answer to the same number of significant figures as the measurement with the least number of significant figures.

Addition and Subtraction Rule

your answer must have the same number of digits to the right of the decimal point as the number with the fewest digits to the right of the decimal.

What is the formula for density

Density = mass/volume

What are the units of density?

g/mL or g/cm3

Concept of Density

Density is a ratio of the mass of an object to the volume of the object

What is the formula for volume?

V=M/D

What is the Mass formula

M = D x V

Density graphing

The slope is the same as the density

Slope Calculation

Slope = y2 - y1 / X2-x1

What is the effect of sample size on the density of a material?

Sample size does not affect density.

Matter

Everything in nature that has mass and volume

Substance

Metter with a uniform composition , has a single formula

Mixture

Matter that is a physical combination of 2 or more substance

Element

Simplest substance cannot be broken into simpler fragments

Compound

A substance formed by the chemical combination of 2 or more elements

Homogenous Mixture or Solution

A physical combination of 2 or more substance mixed unifromly has a single phase

Heterogeneous Mixture

A pysical combination of two or more substances, not blended uniformly , ingredientes remain distinct

Example of Heterogeneous Mixture

Sand, and water oil and water , salt and pepper

Example of Homogenous Mixture or Solution

salt water,gatorade

Example of a Compound

NaC1, C2 H2 OH

The difference between A substane and mixture

Physicals change

The difference between an element and compound

Chemical change