Chemistry Midterm Test Questions – Flashcards
Unlock all answers in this set
Unlock answers| example of qualitative observation |
black table descriptions |
| example of quantitative observation |
3" pencil quantity observation |
| theory |
| a set of hypothesis that gives an overall explanation of some part of nature |
| law |
| generally observed behaviors summarized into a statement |
| atom |
| fundamental unit of which elements are composed |
| _________tells what happens and _________ is our attempt to explain why it happens |
law theory |
| the law of constant composition applies to________ |
| compounds |
| the fundamental particle according to Dalton |
| atom |
| The 1st scientist to show that atoms emit tiny negative particles |
| JJ Thomson |
| the tiny negative particles |
| electrons |
| which atomic particle determines the chemical behavior of an atom |
| nucleus |
| The scientist whose alpha-particle scattering experiment led him to conclude that the nucleus of an atom contains a dense center of positive charge |
| Ernest Rutheford |
| positive particle |
| proton |
| what 2 scientist discovered the neutron |
| James Chadwick and Ernest Rutheford |
| atoms with same # of protons but different # of neutrons |
| isotopes |
| mass # = |
| protons + neutrons |
| the # of protons in the nucleus of an atom |
| atomic # |
non metal alkali metal alkali earth metal noble gas halogen
|
| [image] |
| elements right next to stair step like in periodic table |
| metalloids |
| lanthanides and actinides are periods also called |
| rare earth metals |
| different form of a given element |
| isotopes |
| Isotopic symbol |
The normal chemical symbol is used for the isotope with the addition of the atomic number (Z) at the lower left of the symbol and the atomic mass number (A) at the upper left as shown [image]X. |
| who is given the credit for the developing the periodic table of elements |
| Mendeleev |
| naming binary compounds |
1. Write the name of the element represented by the first symbol in the formula. 2. Write the name of the element represented by the second symbol in the formula, but change the ending of the element's name to "ide". 3.; Check a reference table to determine the number of positive oxidation numbers that the first element forms.; If it only forms one then you are done. 4.; If the first element shows more than one oxidation number, than use the stock system.; Determine the oxidation number that the first element is showing and write that roman numeral in-between the two elemental names. |
| Rules for Naming Acids that;Do Not Contain Oxygen;in the Anion: |
| Rules for Naming Oxyacids (anion contains the element oxygen) |
| Naming Polyatomic compounds |
;The cation is written first in the name; the anion is written second in the name. |
| ;electronegativity |
the measure of the attraction of an atom for the electrons in chemical bond ----increases l decreases |
| ionization energy |
energy required to completely remove an electron from an atom or ion -----decrease l increase |
| how to determine p/e/n in ions |
p remains the same n remains the same e changes according to number + = subtract - = add |
| pure substance |
| A sample of matter, either an element or a compound, that consists of only one component with definite physical and chemical properties and a definite composition. |
C and c physical and chemical properties |
| Physical properties are charecteristics of a pure substance that can be observed without changing it into another substance. Chemical properties are charecteristics of a pure substance that describes its ability to change into different substance. |
c and c physical and chemical change |
| A chemical property is a characteristic of a substance that is observed when it undergoes a chemical change. 1) Physical properties are properties of an element or compound that can be observed without a chemical reaction of the substance. Density and electrical conductivity are examples of physical properties. |
| solids |
| Solids - Keep their shape Definite mass ( will not change in size ) Definite volume ( will not change shape ) High melting point Molecules vibrate slowly in place |
liquids
|
| Liquids - Take shape of container Definite mass Indefinite volume ( will change in shape under certain conditions ) Molecules vibrate rapidly and freely |
gases
|
| Gases - Take shape of container and fill completely Indefinite mass and volume Expand rapidly and evenly to fill container When released in large area ( class room, outside, outer space, ) will fill entire area and become extremely scarce. |
