physical science midterm

the steps commonly used by scientists to test hypotheses and solve problems are called

scientific method

what is the information gathered from an experiment called

data

The part of an experiment in which all conditions are kept the same is the what

control group

a scientific explanation that has never been disproved is called what

law

if you are taking measurements of the height of seedlings in an experiment, you are collecting what

quantitive data

if you are writing about colors and shapes of leaves, you are collecting what

qualtitative data

rules and patterns of nature are using which type of reasoning

inductive reasoning

what do you use to examine the world around you

your senses

what are the 3 parts of a proper hypothesis

if, then, because

name an example of scientific theory and law

theory: big bang theory
law: newtons law of motion

draw and label the proper set up for a graph. what piece of information goes on the x axis? what goes on the y axis?

x axis: independent variable
y axis : the dependent variable

which graph would you use if you are comparing the rate of change between trial subjects/objects over time?

line graph

List in order the steps of the scientific method

observation/ask a question, gather background information, form a hypothesis, design an experiment, collect and analyze data, draw conclusions, and communicate results

anything that has mass or takes up space

matter

the measure of earth gravity acting on an object

weight

a combination of 2 or more substances that are physically combined in changeable ratios

mixture

matter that can flow

fluid

a mixture that is cohesive throughout. looks as if it is one substance

Homogeneous Mixtures

what is a heterogenous mixture

a combination of substances where the composition is not uniform throughout sandwitch

what is the viscosity of liquid

its resistance to flow

What are physical properties?

Characteristics that can be observed without changing the identity of the substance

What is a physical change?

a change in look or form, but not a new substance

What are chemical properties?

how a substance interacts with other substances

What is a chemical change?

A change in matter that produces one or more new substances

what are the states of mater and their characteristics

Solid: Has a definite shape and volume, with particles tightly packed together and vibrating in fixed positions

Liquid: Has a definite volume but takes the shape of its container, with particles able to move past each other while still being attracted

Gas: Has neither a definite shape nor volume, with particles moving rapidly and randomly with little attraction to each other

plasma: gas is so heated that some of its electrons become free from their atoms

which state of matter has vapor pressure

gas

the building block of all matter

an atom

the most widely accepted workable model of matter is called what

the particle model

which state of matter has fast moving particles? so fast they can create electrical charges

plasma

what causes different liquids to vary in viscosity

the strength of intermolecular forces between their molecules

give two examples of non matter

light and sound

list 3 pieces of evidence that led to the acceptance of the particle model of matter

brown, changes in motion, law of definite proportion

give one example for the following:
element
compound
pure substance
heterogenous mixture
homogenous mixture

element: hydrogen
compound: H2O/water
pure substance: gold
hetero: oil and water
homo: air

draw and label the 4 states of matter and how they interact with one another

plasma off to the side

what is the formula for density

Density = mass/volume

know how to find density, mass, and volume

d=m/v (g/cm3)
m=dxv (g)
v=m/d (cm3)

How do Aristotle's model of matter and the particle model of matter represent matter?

Aristotle- continuously devisible
particle model- tiny indivisible particles

which scientists is associated with the discovery of electrons

Thompson

which scientist created the first modern atomic model

dalton

which scientist is credited with the discovery of the nucleus

rutherford

which model of the atom says that atoms are made of dense, positively charged central nucleus surrounded by negatively charged electrons

bohr model

this model of the atom says that atoms are made of a dense, positively charged central nucleus surrounded by negatively charged electrons

nuclear model

the observation that opposite charges repel each other

law of electrostatic charges

unequal numbers of protons and electrons giving that atom a charge is known as a(n)

ion

what is an anion

A negatively charged ion

what is a cation

A positively charged ion

why is the Bohr model still used, even though it is not completely accurate in its description of the atoms structure

it provides a simple, visual representation of atomic structure

List all subatomic particles and where their corresponding charges

Proton: Positive charge (+1)
Neutron: Neutral charge (0)
Electron: Negative charge (-1)

atoms of the same element with differing numbers of neutrons are called what

isotopes

what are the 3 types of naturally occurring carbon atoms? which is radioactive

carbon-12, carbon-13, and carbon-14, with carbon-14 being radioactive

the smallest unit of matter is what

an atom

which scientist demonstrated fire could not be an element

laosier

How did the idea of triads influence the development of the periodic table, even though more than three elements share similar properties?

Triads showed a pattern in element properties, hinting at order, which helped develop the periodic table.

the unique feature of mandeleevs classification method was that he

left gaps in his periodic table to accommodate elements that were not yet discovered

which scientists discoveries led to organizing the periodic table using atomic number rather than atomic mass

Moseley

the modern periodic table has. how many periods and how many groups

7 periods and 18 groups

How would a highly conductive, malleable, and lustrous solid most likely be classified?

metal

which of the following correctly arranges the elements from smallest atomic radius to largest
A. barium, beryllium, magnesium, strontium
B. barium, magnesium, strontium, beryllium
C. barium, strontium, magnesium, beryllium
D. beryllium, magnesium, strontium, barium

D. beryllium, magnesium, stontium, barium

what affects the size of an elements atomic radius

the number of electron shells it has

what is electronegativity? where would you find the largest amount on the table?

a measure of an atom's ability to attract shared electrons in a chemical bond. top right corner

the development of the modern periodic table came as a result of what?

-organize the elements
- similar atributes
- structure of the atom

the modern periodic table arranges elements according to what

atomic number

elements in the same _ on the periodic table have the same number of valence electrons

group

Where are nonmetals located on the periodic table?

right of staircase

uranium, found below the main body of the periodic table, is best classified as what

an actinide

what is the family name for the group containing chlorine

halogens

which of the following has the largest atomic radius?
A. sodium
B. argon
C. cesium
D. radon

cesium

Which of the following correctly arranges the elements from greatest electronegativity to least?
A. carbon, fluorine, lithium, nitrogen
B.fluorine, nitrogen, carbon, lithium
C. lithium, carbon, nitrogen, fluorine
D. nitrogen, fluorine, carbon, lithium

B. fluorine, nitrogen, carbon, lithium

ancient greeks thought that all matter in the universe was made of only 5 elements

true

the symbols that represent each elements must always use two letters

false- only some

alkaline-earth metals are slightly more reactive than alkaline earth metals

false- they are less reactive

elements with more protons and electrons almost always have larger atomic radii then those with fewer protons and electrons

true

demonstrated that combustion requires the presence of oxygen

Lavoisier

developed the law of octaves through arranging elements by atomic mass

Newlands

first recognized groups of three elements with similar elements

Johann Wolfgang Döbereiner

led to reorganizing the period table on the basis of atomic number

Mosele

organized elements with similar characteristics in columns like the modern periodic table used letters to represent each element and superscripts to represent the number of atoms

mendeleev

how did Mendeleev use his periodic table to predict future discoveries of unknown elements

he left gaps

because groups 3-16 contain metals, non-metals, and metalloids, they are known as what

mixed groups

the measure of an elements ability to attract and hold electrons when bonded to other atoms is called what

electronegativity

would you expect fluorine or iodine to act more like a nonmetal? explain.

Fluorine would be expected to act more like a nonmetal compared to iodine because fluorine is more electronegative

what are the rules and characteristics of chemical bonding?

rules- octet rule
characteristics- strength, polarity, reactivity, and shape

the octet rule states that atoms are generally more stable when

they have eight electrons in their valence shell

the properties of water are different than hydrogen and oxygen because

when they chemically combine the create a whole new molecule

covalent bonding forms _ while ionic bonding forms _

covalent- 2 non metals
ionic- 1 metal 1 non-metal

why does diatomic nitrogen form a triple bond

each nitrogen atom has five valence electrons

what type of atom is most likely to take valence electrons in ionic bonding

a nonmetal atom

write the lewis structure for potassium fluoride

[K+] [F-]

how many atoms are represented by the chemical formula CuSO4

6

what is the chemical structure for potassium nitride

K₃N

most atoms are unstable when bonded to other atoms

false- most atoms become more stable when they form bonds with other atoms

molecules form only when different elements bond together

false- molecules can form when any elements bond together

Only one covalent bond can exist between two atoms.

false- multiple covalent bonds (double or triple) can also exist between the same two atom

electrons shared in covalent bonds are not necessarily shared

false- the sharing isn't always equal between atoms

a superscript on a chemical formula indicates the number of atoms

a superscript usually represents the charge of an ion.

metals can only have one oxidation state

most metals can have more than one oxidation state

between oppositely charged ions

ionic

between atoms with very different electronegativities

ionic

between elements such as transition metals with similar low electronegativities

metalic

most often formed between non-metals

covalent