LTHS Chemistry Midterm – Flashcards
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Unlock answers| steps of the scientific method |
1. observation 2. hypothesis 3. perform experiment 4. repeat |
| hypothesis vs. theories |
hypothesis: not proven theory: almost fact, has been tested with many experiments |
| theory vs. law |
theory: can change law: it's true |
| physical property: definition and;examples? |
| something that can be observed w/o performing a chemical change: color, 5 cm long |
| chemical change vs. physical change |
chemical change=must change actual atoms composition physical change=can be reversed |
heterogeneous mixture? |
you can see difference between particles in mixture |
| .;;;;;; What is the common name for a homogeneous mixture? |
| solution |
;Describe how the process of distillation works. |
| has to do with boiling water and evaporating water and stuff is left behind |
| difference between element, compound,;and mixture |
element=1 element compound=2+ elements (usually will be a written out compound) mixture=2+ elements (usually a common object) |
| law of conservation of mass and energy |
| mass and energy are neither destroyed or created |
| observation vs. inference |
observation: you see it happen inference: an opinion/don't actually observe it |
| qualitative and quantitative observations |
qualitative: w/o numbers quantitative: with numbers |
accuracy vs. precision |
accuracy:close to actual answer (if actual answer is 3, accuracy is 3,3.5,4,2) precision:answers close together to each other (if answer=3, precision is 8,9,10,11) |
know how to write in scientific notation try: 30000 and .0005 |
30000=3.0 x 10^4 .0005= 5.0 x 10^4 |
KNOW RULES FOR SIG FIGS |
Name the metric unit for: a. mass b. volume c. length d. heat |
A.grams B.liters C.meter D.celcius |
| difference between mass and weight |
mass: how much matter is in an object weight: mass and gravity together |
| density of water |
| 1 gram per mL |
| how can you predict if something will sink or float? |
if it has a density less than water, it will float but, more, and it will sink. |
put these in order from largest to smallest meter, hectameter, centimeter, decimeter, millimeter, kilometer, dekameter |
kilometer, hectameter, dekameter, meter, decimeter, centimeter, millimeter
(Karen hailed down 1 darn cab, man!!) |
An element with an equal number of protons and electrons is called a(n)______. |
| atom |
metalloid |
the elements surrounding the squiggly line on the periodic table of elements. |
| binary vs. ternary |
binary=2 elements ternary=3+ elements |
| acid, molecular, ionic |
acid-starts with hydrogen molecular-2 nonmetals ionic-metal and nonmetal |
| conversion of moles to L |
| 22.4 L to moles |
| empirical or molecular |
| i don't know the difference... |
| double replacement, single replacement, decomposition, combustion, synthesis |
synthesis=coming together double replacement=cations switch single replacement=cation switches with other decomp=breaks down combustion=products are H20 and CO2 |
; |
| H20 and CO2 |
What dangerous products are formed through incomplete combustion? |
CO |
STUDY HOW YOU KNOW IF RXN's WORK!!! |
study pink sheet
|
| catalyst |
| speeds up a Rxn |
| exothermic reaction vs. endothermic reaction |
exo-energy given off, number is a product, delta H is negative endo-energy absorbed, number is a reactant, delta H is positive |
LOOK OVER NOMENCLATURE. |
