250,000 grams is ________ kilograms
250
A testable explanation of an observation that predicts an outcome.
hypothesis
The state of matter that is composed of atoms loosely packed together.
What is a liquid?
What is the number of protons plus the number of neutrons?
Atomic Mass
A covalent bond is formed between...
2 non-metals
The speed of light is about 300,000,000 m/s. What is the correct expression in scientific notation?
3.0 x 10^8 m/s
Group used for comparison with the experimental group; nothing changes for this group
control
Matter that is composed of atoms tightly packed together.
What is a solid?
Atomic number is the same as the number of ----
the number of protons
A substance that cannot be broken down by ordinary means
element
The liquid has a temperature of 100 degrees Celsius. Quantitative or qualitative?
Quantitative
What temperature scale should be used to measure metric freezing point?
Celsius
States of Matter
What is solid, liquid and gas?
Number of Electrons is the same as the Number of ----
protons
What is the smallest unit of an element?
an atom
Which instrument would most accurately and precisely determine the mass of a toy car?
triple beam balance
Explain the difference in independent and dependent variables.
independent=scientist changes, x axis
dependent=effect of independent, measured or observed, y axis
The four major phase changes.
What are freezing, Melting, condensation, and evaporation?
Atomic Mass - Atomic Number = number of _____
neutrons
Where are the electrons located that are most responsible for chemical reactions?
outer shell; valence
Put in order from smallest to largest: mili, deci, centi, kilo, (meter/liter/gram), hecto, deka
kilo, hecto, deka, (meter/liter/gram), deci, centi, mili
What are 3 examples of a physical change?
answers will vary
A loss of heat.
Freezing or boiling?
Freezing
A -2 ion has gained ____ electrons.
2
Describe the difference in a mixture vs. compound
mixture-physically combined
compound-chemically combined