a proposed explanation for an observation that has not been tested yet
What is hypothesis
100
the state of matter that has a definite volume but not a definite shape.
What is a liquid
100
write this number in scientific notation: .000450
What is 4.50 X 10 (-4)
100
the subatomic particle that is not found in the nucleus.
What is the electron.
100
the temperature scale that is based on the movement of the particles in the matter.
What is the Kelvin scale.
200
a measure of the amount of space an object takes up
What is volume
200
the state of matter that has the highest compressibility.
What is gas (the particles are spread out the farthest)
200
how many significant figures does this number contain: 0.003050.
What is 4.
200
the scientist that is credited with the discovery of a nucleus in the atom.
What is Rutherford
200
round this number to 4 significant digits: 50.13656
What is 50.14
300
give an example of an intensive property and an extensive property of a copper penny.
What is intensive: shiny, brown, hard
extensive: 2.5 g (mass), volume
300
A salad would be classified as a _____ mixture, while a glass of sweat tea would be classified a _______ mixture.
What is heterogeneous, homogeneous
300
the number of km in 4,567 dm?
What is .4567 km
300
list the number of protons, neutrons, and electrons in a Carbon-14 atom. Classify the atom as neutral, an ion, or an isotope.
What is protons:6, electrons: 6, neutrons: 8. isotope
300
list the three subatomic particles, where they are found, their charge, and their relative mass
What is electron- in electron cloud, negative, 0 mass
proton- in nucleus, positive, 1 amu
neutron- in nucleus, neutral, 1 amu
400
_______________ describes what happens in nature as observed by many observations and experiments, while a ________ attempts to explain why these set of observations occur.
What is scientific law, theory
400
The melting of ice is an example of a ____ change, while the splitting of water into hydrogen and oxygen is a ____ change.
What is physical, chemical
400
the known density of aluminum is 2.7 g/ml. If students in the lab calculate the density of aluminum three different times and record the density as 4.5,4.45,4.56, are these measure precise and/or accurate?
What is the measures have a high precision, but low accuracy.
400
describe what Rutherford shot at the piece of gold foil and his results that were suprising (be detailed, not what he discovered)
What is alpha particles (positively charged) most passed straight through or had minor deflections as expected, the surprising result was that some shot right back at him.
400
report your answer with the correct number of significant digits: 13.34 X .00240 X 2.014
What is .06448 = .0645
500
An experiment tests to see if the color shirt a student wears to take their exams affects their performance on the exam. Identify the independent variable and the dependent variable.
What is independent- color of shirt, dependent- performance on the exam.
500
the four ways to recognize that a chemical change has occurred
What is change in color, bubbles and production of a gas, formation of a precipitate, heat or light energy given off
500
A technician measures the boiling point of octane to be 124.1 degrees Celsius. The actual boiling point of octane is 125.7 degrees Celsius. Calculate the percent error.
What is 1.273%.
500
Explain how the model of the atom changed from Dalton to Thomson to Rutherford.
What is Dalton- solid sphere, not made of anything else
Thomson- plum pudding model, electrons evenly distributed
Rutherford- dense positively charged nucleus with electrons surrounding it
500
A gold- colored bar of metal has a mass of 57.3 g. The bar has a length of 2.5 cm, a width of 1.5 cm, and a height of 1.25 cm. If the density of gold is 19.3 g/cm3, do you think this bar is pure gold? Provide math calculations to support your answer.
What is density of the bar: 12.3 g/cm3 ( mass= 57.3, volume= 4.7 ) the bar is NOT gold.