Question | Answer |
the periodic table is made of? | periods and groups. |
what are the two main sections of the periodic table? | metals and nonmetals. |
metal is an element that? | is a good electrical conductor and a good heat conductor. |
what metal is a liquid at room temperature? | mercury. |
boiling point of copper? | 2567 degreees celsius. |
many nonmetals are what at room temperature? | gases. |
phosphorus is one of the how many solid nonmetals? | five. |
metalloids have some characteristics of what and what? | metals and nonmetals. |
the study of the compositon, structure, and properties of matter is? | chemistry. |
all matter has? | mass. |
a logical approach to solving problems that len themselves to investigation? | the scientific method. |
testable statement that serves as the basis for predicitions and experiments? | hypothesis. |
mesurements for science? | SI system. |
weight is a measure of what on matter? | gravitational pull. |
density is the ratio of what to what? | mass to volume. |
what is used to convert from one unit to another? | conversion factors. |
what is the closeness of a measurement to the correct or accepted value? | accuracy. |
difference between the experimental value and the accepted value? | percentage error. |
all digits known with certainty plus one final digit, which is uncertain is? | significant figures. |
what factors are completely certain? | conversion factors. |
atoms have been around since the time of? | ancient greeks. |
who proposed the scientific theory of atoms? | John Dalton. |
matter and mass cannot be what in chemical reactions? | created or destroyed. |
cathode-rays supplied evidence of? | electrons. |
what are negatively charged subatomic particles? | electrons. |
Rutherford found evidence of? | atomic nucleus. |
how did rutherord find atomic nucleus? | bombarding metal foil with a beam of positively charged particles. |
atomic nuclei are composed of? | protons. |
atomic number of an element is equal to? | number of protons of an atom of that element. |
the mass number is equal to? | the total number of protons and neutrons in the nucleus. |
what is the total number of electrons need to fill the first two main energy levels? | 10. |
atomic sublevel with the nest highest energy after 4p is? | 5s. |
because excited hydrogen atoms always produce the same line-emission spectrum, scientists concluded that hydrogen? | released photons of only certain energies. |
number of orbitals for the d sublevel is? | 5. |
emission of electrons from metals that have absorbed photons is called the? | photoelectric effect. |
main energy levels of an aom are indicated by? | principal quantum numbers. |
main energy level that can hold only 2 electrons? | first. |
one of the wave properties of electromagentic radiation, such as light, is? | frequency |
in SI, the frequency of electromagnetic radiation is measured in? | hertz. |
for the f sublevel, the number of orbitals is? | 7. |
Mendeleev noticed the properties of elements usually repeated at regular intervals when the elements were arranged in order of increasing? | atomic mass. |
what are the radioactive elements with atomic numbers from 90 to 103 in the periodic table called? | actinides. |
the discovery of noble gases changed mendeleev's periodic table by adding a new? | group. |
what are the elements with atomic numbers from 58 to 71 in the periodic table called? | lanthanides. |
to which group do potassium and lithium belong? | alkali metals. |
elements in a group or column in the periodic table can be expected to have similar? | properties. |
mendeleev predicted that the spaces in his periodic table represented? | undiscovered elements. |
in the modern periodic table, elements are ordered according to? | increasing atomic number. |
the most useful source of general information about the elements for anyone associated with chemistry is a? | periodic table. |
argon, krypton, and xenon are? | noble gases. |
a mutual attraction between the nuclei and valence electrons of different atoms that bind the atoms together is called a(n)? | chemical bond. |
the elements involved in the formation of a chemical bond are called? | valence electrons. |
atoms are ____ when they are combined? | more stable. |
the chemical bond formed when two atoms share electrons is called a(n)? | covalent bond. |
if two covalently bonded atoms are identical, the bond is? | nonpolar covalent. |
when atoms share electrons, the electrical attraction of an atom for the electrons is called the atom's? | electronegativity. |
if the atoms that share electrons have an unequal attraction for the electrons, the bond is called? | polar. |
a covalent bond results when ___ are shared? | electrons. |
a neutral group of atoms held together by covalent bonds is a? | molecule. |
a ___ shows the types and numbers of of atoms joined in a single molecule of a molecular compound? | molecular formula. |