Chapter 1 A Flashcards
(21 cards)
Scientific Method
7 Steps
Question Research Hypothesis Procedure/Method Data Observations Conclusion
Define Chemistry
Define Matter, and what it is composed of
the study of matter and the changes it undergoes
Anything that has mass and takes up space.
- molecules
- ions
Physical Change
A change in the physical proprties or phase that do not change the composition of a substance
ex: melting ice, evaporating water, crumbling paper
Chemical Change
change in the composition of a substance, a chemical reaction takes place ex: burning paper, decomposing water
What does a chemical change alter?
alters the makup of the substance
- reactivity changes
- heat , light, or electirical energy is often emitted or absorbed
States of matter
Solid, Liquid Gas
How are the molecules in a solid, liquid and gas?
solid, molecules are tightly packed together and locked in a relative position, strong attraction forces next to them, incompressible
LIQUID- No definate shape, definate volume, close particales but can move freely
moderate forces of attraction
GAS- no shape or volume can squeeze into a small spcae weak attraction between particles, particles are constantly moving compressible Ex: air in bicycle tire
Pure substance
Mixture
h2o, NaCl Salt, its properties can be defined
2 different substances with different properties
homogeneous
Heterogenous
together, uniform, a substance that has uniform composition throughout the sample. Evenly distributed
Different, its composition vaires, ex: sand in water, chalk in water milk straight from a cow the particles are different in the mixture
How many elements are there
116
define molecule
smallest sample of a compound that still remains the properties of that compoound
Water has properties. What happens when they are not chemically combined? H and )
Hydrogen and O2 are floating around without being combined hydrogen is an explosive gas, put a match it will butn but if you combine them 2 to 1 ratio you will get water
reactants-> products
Define BOTH
Reactant= one or more starting materials. Between reactants, the + can be read as “reacts with”
Products= one or more substances formed as a result of a chemical reaction.
What is Co and CO
Cobolt= silver metal
Carbon Oxygen= 1-1 ration poisonour orderless gas
H Na He Mg Li Al Be Si B P C S N Cl O Ar F K Ne Ca
Hydrogen Sodium Helium Magnesium Lithium Aluminum Beryllium Silicon Boron Phosphorus Carbon Sulfer Nitrogen Chlorine Oxygen Argon Fluorine Potassium Neon Calicum
Au Ba Bi B Br Co Fe I Mn Ni Pb Pt Rn Ti Zn
Au-Gold Ba-Brium Bi-Bismuth B-Baron Br-bromine Co-Cobolt Fe-Iron I-Iodine Mn-Manganeese Ni-Nickle Pb-Lead Pt- Platinum Rn- Radon Ti-Titanium Zn-Zinc
Formula for Water, Table sugar and Methane
h2o, c12h22011, ch4
Properties of metals
- Grey and silver,
- Malleable, can change shape when hammered
- Luster, can reflect light
- solid at room temperature
- Good conductors of heat and electricity
- Ductile- can be stretched or drawn int a wire
Properties of on metals
Most reactive non metal
Lack Luster Brittle Many are solids or gasses poor conductor of heat and electricity florine
Nitrogen
Bromine
Sulfer
Nitrogen constitutes almost 80% of air and is a colorless gas at room temperature.
Bromine is a red liquid
Sulfer is a yellow solid, found in large underground deposits
Where are the metalloids?
On the staircase, 7 of them
