Unit 1
Which characteristics best describe scientific thinking?
curious, open-minded, and skeptical
Two balls of the same mass are thrown at different velocities. Ball A has a higher velocity than Ball B.
Which statement best describes the kinetic energy of the balls?
Hint: KE = 1/2mv2
Ball A has a higher kinetic energy than Ball B.
Which answer choice correctly names the element that Mendeleev predicted would be discovered and placed in the aluminum column?
gallium (Ga)
What function does adding a coefficient in a chemical equation serve?
It balances the equation, ensuring each side of the reaction has an equal number of atoms.
Which characteristic describes mixtures?
They can be separated through physical means.
Which of the following measurements uses a derived unit?
volume
Which of the following statements accurately describes energy during the phase change of freezing?
Energy is released.
Which answer choice correctly describes why metals are good conductors of thermal energy?
Their atoms have free-floating electrons that easily pass kinetic energy throughout the metal.
What type of reactions release energy into the environment?
kinetic
What substance is insoluble in water?
quartz
Which of the answer choices names a substance that consists of one type of atom?
an element
When the mass of a fluid increases, what happens to the pressure it exerts on objects?
The pressure it exerts on objects increases.
Which answer choice correctly describes a chemical bond?
a force that holds atoms together in a fixed yet flexible structure
Which happens to energy during endothermic reactions?
Energy is absorbed from the environment.
Examine the equation.
HF + KOH ā H2O + KF
What process is shown in the chemical equation?
neutralization
Which of the answer choices best describes the property of volume?
the amount of space a substance's matter occupies
Which names a subatomic particle that is found in the nucleus of an atom?
neutron, proton
Which of the following statements about metalloids is true?
Metalloids have properties that fall between those of metals and nonmetals.
Which type of radiation can penetrate the most barriers, and why?
gamma radiation, because it travels the fastest
Someone adds 20 g of liquid water to 10 g of liquid methanol. Which substance is most likely the solvent?
Water is the solvent because there is more of it.
A testable hypothesis provides a prediction and explanation and can be _____ using a well-designed experiment. (Select all that apply.)
rejected, confirmed
Which answer choice names the subatomic particle that has the least amount of mass in an atom?
electron
Which of the following statements best describes how Moseley's research affected the periodic table?
It became organized by atomic number instead of atomic mass.
Examine the following equation.
10n+23592Uā310n+9236Kr+14156Ba+energy
Which type of nuclear reaction does the equation represent?
nuclear fission
Which of these molecular properties makes water (H2O) a polar solvent?
The oxygen (O) atom holds the electrons in the covalent bonds more closely than the hydrogen (H) atoms and develops a partial negative charge.