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Common Knowledge
Multiple Choice
Thinking Questions
Miscellaneous
100
All atoms of an element have the same number of _______.
What is protons.
100
The SECOND electron shell of an atom can hold a maximum of ______ electron(s).
What is 8.
100
Sweat on Heather's forehead and arms formed drops because of the a. cohesive nature of water b. high salt content of sweat c. ability of water to moderate heat d. high evaporative cooling effect of water
What is a. cohesive nature of water.
100
Human body cells are approximately ____ water.
What is 70-95%
100
A base does what to a solution? (ions)
What is removes H+ ions from a solution.
200
Nitrogen has atomic number of 7; therefore, it has ____ electrons in its outermost electron shell.
What is 5.
200
An atom with an electrical charge is a(n) _________.
What is ion.
200
Sugar dissolves when stirred into water. The sugar is the _____, the water is the ______, and the sweetened water is the ________. a. solute...solvent...solution b. solution...solvent...solute c. solution...solute...solvent d. solvent...solute...solution
What is a. solute...solvent...solution
200
What happens to its molecules when water freezes?
What is its molecules move furthe apart.
200
Which of the following is an acid? HCl, NaOH, CH4, or NaCl.
What is HCl.
300
Sweating cools your body by _________.
What is evaporative cooling.
300
What is the name given to substances that resist changes in pH?
What is buffers.
300
Isotopes of an element have the same number of ____ and different numbers of _________. a. neutrons...protons b. electrons...protons c. protons...electrons d. protons...neutrons
What is d. protons and neutrons
300
The four most common elecments found in living things are what?
What is C, O, N, H
300
__________ is an example of an element. a. salt b. carbon c. water d. glucose
What is carbon.
400
The name given to bonds that involve the sharing of electrons is called _________.
What is covalent.
400
The tendency of molecules of the same kind to stick together is called ___________.
What is cohesion.
400
An atom with a positive charge has _____. a. more protons than electrons b. more protons than neutrons c. more electrons than protons d. more neutrons than protons
What is a. more protons than electrons
400
The lower the pH of a solution, the ____________
What is the more acidic the solution.
400
Whay is water considered a polar molecule?
What is The oxygen end of the molecule has a slight negative charge, and the hydrogen end has a slight positive charge.
500
The hydrogen and oxygen of a water molecule are held together by __________ bonds.
What is covalent.
500
Adjacent water molecules are joined by _____ bonds.
What is hydrogen.
500
When a base is added to a buffered solution, the buffer will ______. a. accept water molecules b. donate H+ ions c. form covalent bonds with the base d. donate OH- ions
What is b. donate H+ ions
500
Why (if you are careful) are you able to float a needle on the surface of water?
What is The surface tension that is a result of water's cohesive properties makes this possible.
500
The atom's _____ are found in its nucleus.
What are neutrons and protons.