Module 2 Flashcards
(57 cards)
What is the difference between the continuous theory of matter and the discontinuous theory of matter?
the continuous theory of matter states that matter comes in long, continuous sheets. the discontinuous theory of matter assumes that matter comes in little packets and the only reason matter looks continuous is that we cannot magnify it enough to see the little packets off matter.
What 2 laws were instrumental in the development of Dalton’s atomic theory? What law did Dalton predict using his theory?
1) The law of mass conservation 2) the law of definite proportions.
Dalton predicted the law of multiple proportions.
Describe how the law of mass conservation can be used to explain the result of experiment 2.1.
Matter cannot be created or destroyed. Throughout the chemical reaction that occurs in experiment 2.1, the total mass before the reaction must equal the total mass after the reaction. The mass measurement on the scale should not change during the reaction.
List the 4 assumptions of Dalton’s atomic theory. which of the assumptions are wrong? Why?
1) All elements are composed of small, indivisible particles called atoms
2) All atoms of the same element have exactly the same properties.
3) Atoms of different elements have different properties
4) Compounds are formed when atoms are joined together. Since atoms are indivisible, they can join together only in simple, whole-number ratios.
1 and 2 are wrong. Atoms are not truly indivisible and the mass of the atoms can change within the elements.
what is the difference between:
1) an atom and an element?
2) a molecule and a compound?
3) an atom and a molecule?
4) an element and compound?
1) elements are made of identical atoms
2) Compounds are made of identical molecules
3) An atom is the smallest unit of matter. A molecule is also a unit of matter, but it is formed when atoms join together. A molecule is made up of more than one atom
4) Elements are made of identical atoms while compounds are made of identical molecules.
What are the physical characteristics that distinguish metals from nonmetals?
Metals are malleable, have luster, and conduct electricity.
Nonmetals are brittle, lack luster, and do not conduct electricity
How can you determine whether an atom is a metal or a nonmetal from the periodic table? Are there any exceptions?
A heavy jagged line runs down the right side of the chart. An atom is on the left of the line it is a metal. To the right of the line is a nonmetal. Hydrogen is the exception: it is on the left of the line but it is not a metal.
How can you experimentally determine whether a compound is ionic or covalent?
Ionic if (when dissolved in water) it conducts electricity. If it does not conduct electricity it is covalent
How can you determine from the periodic table whether a compound is ionic or covalent?
if a compound has a metal in it, it must be ionic. If it has not metals, it is covalent
Which law governs why carbon and oxygen can form 2 different molecules; CO and CO2?
the law of multiple proportions
Why do chemists use 2 different naming systems for compounds?
because ionic and covalent compounds join atoms together differently. Ionic compounds only have one possible combination of atoms. Covalent compounds have many possible combinations.
If a substance can be physically separated into its components, is it a pure substance or a mixture?
mixture
If a substance can be given a chemical name, such as calcium bromide, is it a pure substance or a mixture.
a pure substance
What element makes up the majority of the air we inhale
Nitrogen
Describe the difference between quantitative and qualitative measurements.
quantitative measurements is one that is made using a precise and quantifiable measurement process
qualitative measurements is descriptive, subjective, or difficult to measure; it is often an estimated measurement or best approximation
A change that seems to break a molecule apart is called a .
Chemical change or chemical reaction
A students writes this formula for sodium chloride NACL. What is wrong with this formula?
the 2nd letter of an atomic symbol needs to be a lowercase letter.
What are the elements that lie long the jagged line called?
metalloids or semimetals
Describe a dimensionless quantity.
it is a measurement with no units
Why doesn’t distilled water conduct electricity?
There are no charges particles in the water that can carry the electricity.
What is the -ide name for
H C N O F P S Cl Br And I
H-hydride C-carbide N-nitride O-oxide F-fluoride P-phosphide S-sulfide Cl-chloride Br-bromide I-iodide
What are the prefixes for covalent compounds?
Mono-1 di-2 tri-3 tetra-4 penta-5 hexa-6 hepta-7 octa-8 nona-9 deca-10
what is the name of H?
Hydrogen
what is the name of He?
helium
