Question | Answer |
study of the compositon and structure of materials and the changes that materials undergo best describes the science of? | chemistry |
technology is the | application of scientific knowledge to solve problems |
the branch of chemistry that includes the study of materials and processes that occur in living things is | biochemistry |
the state of matter in which a material has neither a definite shape and definite volume is the | gaseous state |
under ordinary conditions of temperature and pressure, the particles in a gas are | very far from each other |
group_______ in the periodic table contains only metals | 2 |
based on their location in the periodic table oxygen and selenium have | similar properties |
the most useful source of chemical information about the elements is a | periodic table |
a vertical column of blocks in the periodic table is called? | group |
Elements in a group in the periodic table can be expected to have similar | properties |
which of the following observations is quantitaive? | the liquid boils at 100 degrees C |
Quantitative observations are recorded using | numerical information |
Standards are chosen because they | are reproducible in another laboratory |
The SI standard units for length and mass are | meter and kilogram |
the symbol for the metric unit used to measure mass is | g |
the symbol that represents the measured unit for volume is | ML |
the SI base unit for time is the | second |
to determine density the quantities that must be measured are | volume and mass |
to calculate the density of an object | divide its mass by its volume |
poor precision in scientific measurement may arise from | both human error and the limitations of the measuring instrument. |
A nuclear particle that has about the same mass as a proton, but with no electrical charge, is called | neutron |
who discovered the nucleus by bombarding gold foil with positively charged particles? | Rutherford |
Experiments with cathode rays led to the discovery of the | electron |
the fact NaCl always consists of 39.34% Na and 60.66%Cl, is what law? | Law of definite proportions |
the smallest unit of an element that can exist alone or in combination with other such particles is an? | atom |
the atomic number of oxygen, 8, indicates that there are eight | protons in the nucleus of an oxygen atom |
what is the atomic number for aluminum? | 13 |
How many half-lives are required for three-fourths of the nuclei of one isotope in a sample decay? | 2 |
Particles or electromagnetic radiation emitted from the nucleus during radioactive decay | is nuclear radiation |
Gamma Rays are | Electromagentic waves |
The distance between two sucessive peaks on a wave is its | Wavelength |
An element with 8 electrons in its highest main energy level is a | noble gas |
Which group are the Noble gases? | 18 |
What is the total number of electrons needed to fill the first two main energy levels? | 10 |
The atomic sublevel with the next highest energy after 4p is | 5s |
For an electron in an atom to change from the ground state to an excited state, | energy must be absorbed |
the number of orbitals for the d sublevel is | 5 |
A quantum of electromagnetic energy is called a | photon |
For electromagnetic radiation, c (the speed of light) equals | Frequency times wavelength |
The main energy levels of an atom are indicated by the | Principal quantum numbers |
What are the radioactive elements with atomic numbers from 90 to 103 in the periodic table called? | The actinides |
The discovery of the 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? | The lanthanide elements |
To which group do lithium and potassium belong? | Alkali metals |
Mendeleev predicted that the spaces in his periodic table presented | 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 |
One-half the distance between the nuclei of identical atoms that are bonded together is called the | atomic radius |
To which group do fluorine and chlorine belong? | Halogens |
The electrons involved in the formation of a chemical bond are called | Valence electrons |
Most chemical bonds are | Partly ionic and partly covalent |
In a molecule of flourine, the two shared electrons give each flourine atom _____ electron(s) in the outer energy level | 8 |
In drawing a Lewis structure, each nonmetal atom except hydrogen should be surrounded by | 8 electrons |
An octect is equal to | 8 |
A compound that vaporizes readily at room temperature is most likely to be a(n) | molecular formula |
A ____ shows the types and numbers of atoms joined in a single molecular of a molecular compound | Molecular formula |