Chemistry midterm

What is the charge of a cation?

a positive charge

If a material contains three elements joined in a fixed proportion, it is a(an)

compound

compounds consisting entirely of nonmetals are

covalent

at least one pair of electrons is shared between atoms forming a

covalent bond

With significant figures, you count from the left when the number is a ______ and from the right when it is a _______

decimal; whole number

proper name for N2O5

dinitrogen pentoxide

P2S3

diphosphorus trisulfide

Which subatomic particle plays the greatest part in determining the properties of an element?

electron

charge of -1

electron

the polarity of a covalent bond is determined by the difference in ___ of the atoms forming the bond

electronegativity

in a polar covalent bond

electrons are not shared equally

the type pf formula that shows the ratios or relative numbers of each type atom present in a compound is a

empirical formula

The most important rule in lab safety is to?

follow instructions

The unit of measure for density is

gm/cm^3

elements with similar properties aligned in vertical columns are called

groups

Salt water is what kind of mixture

homogeneous

A mixture that appears to contain only one substance is a(an

homogeneous mixture

Give an example of a homogeneous mixture and a heterogeneous mixture.

homogeneous- salt water heterogeneous- salad

neutron is located in __ and have a charge of __

inside the nucleus\0

bond where electrons are transferred to form ions that combine

ionic

what type of compounds do metals and nonmetals tend to form

ionic compounds

What is the energy required to remove an electron from an atom in the gaseous state called?

ionization energy

what happens to matter during a chemical reaction

it is neither destroyed nor created

how does the atomic radius change when moving left to right across a period

it tends to decrease

how does atomic radius change from top to bottom in a group in the periodic table

it tends to increase

An example of an SI basic unit is a

kilogram

What is the SI unit of mass?

kilogram

Which state of matter is characterized by having an indefinite shape, but a definite volume?

liquid

what element in the second period has the largest atomic radius

lithium

name of the binary ionic compound of Fluorine with Lithium

lithium fluoride

Which of the following elements is in the same period as phosphorus

magneisium

Write out the Law of Conservation of Mass

mass neither created or destroyed

The sum of the protons and neutrons in an atom equals the ____.

mass number

majority of the elements are

metals

type of formula where the exact numbers of each type of atom present are given

molecular formula

All atoms are ____.

neutral, with the number of protons equaling the number of electrons

The atomic number of an element is the total number of which particles in the nucleus?

neutrons

[Ar}4s^2

noble gas core, principle energy level, sub-level, number of electrons in the suborbital

the elements with the highest inization energies are the

noble gases

element that is a poor conductor of electricity is a

nonmetal`

All atoms of the same element have the same ____

number of protons

Isotopes of the same element have different ____

numbers of neutrons

identify whether the following is a physical or chemical change alcohol evaporating baking a cake leaves changing color butter melting wood rotting

p c c p c

Three different people weigh a standard mass of 2.00 g on the same balance. Each person obtains a reading of 7.32 g for the mass of the standard. These results imply that the balance that was used is ____

precise

each period in the periodic table corresponds to a

principle energy level

located inside the nucleus with a charge of +1`

proton

The atomic number of an element is the total number of which particles in the nucleus

protons

Compounds are what kind of substances

pure

NaNO3

sodium nitrate

What two states of matter occupy a definite volume?

solids; liquids

When an iron nail is ground into powder, its mass ____

stays the same

H2SO4

sulfuric acid

The nucleus of an atom is ____

the central core and is composed of protons and neutrons

compare the relative size of an ion to its neutral atom

the radius of an anion is greater than the radius of its neutral atom

there are exceptions to the octet rule T or F

true

the elements in a group have similar properties because they have the same number of

valance electrons

ZnO

zinc oxide

how many protons are present in neutral atoms of an element with an atomic number of 24

24 protons and electrons

Absolute zero corresponds to

0 k

Which of the following measurements contains two significant figures? 0.000400 0.00404 0.00044 0.004040

0.00044

What is the density of an object having a mass of 8.0 g and a volume of 25 cm^3

0.32 g/cm^3

express 1,360, 000, 000 gm in scientific notation

1.36 gm^9

express 0.000000015 cm in scientific notation

1.5 cm^-8

If 1 gallon = 3.785 liters, how many gallons are in 50 liters

13.2 gallons

dioxide indicates

2 oxygen atoms

In medieval Britain, property was often measured in units such as fardells, nookes, yards, and hides. Using the following conversions, calculate the number of fardells in eight hides. 2 fardells = 1 nooke 4 nookes = 1 yard 4 yards = 1 hide

256 fardells

how many types of chemical bonds are there

3

what is the maximum number of multiple covalent bonds possible

3

Which of the following measurements is the most accurate? 3.1000 3.10000 3.12222 3.000000

3.000000

alpha radiation symbol

4 2 (fish symbol)

How many kilometers are in 26 miles? (1 kilometer = 0.6214 miles)

41.8 km

How many protons, electrons, and neutrons does an atom with atomic number 50 and mass number 125 contain?

50 protons, 50 electrons, 75 neutrons

How many significant figures are in the following measurements 187.032 0.0601 1.30 620

6 3 3 2

An electric current is passed through a 68.3 gram sample of water to separate it into its component parts. If 7.59 grams of hydrogen gas is released, how much oxygen is produced?

60.71 grams

An element has an atomic number of 76. The number of protons and electrons in a neutral atom of the element are ____

76 protons and 76 electrons

group of elements known as noble gases

8A

What happens at absolute zero?

All atomic and molecular motion stops.

larger ionization energy Be or Ba

Be

Who said "there are two types of electric charge: positive and negative"

Benjamin Franklin

carbonate ion

CO3^-2

larger atomic radius Ca or Ca^2+

Ca

"All matter is composed of atoms which are too small to be seen."

Democritus

A substance that is made up of only one kind of atom is a(an)

Element

"Discoverer of the nucleus"

Ernest Rutherford

The metric prefix centi means one thousandth, or 0.001.

False, centi means one hundred, or 0.01

The gram is the SI base unit for measuring mass.

False; kilogram

True/ False? The safety symbol showing a flame should remind you to secure all loose equipment

False; reminds you that a flame is present so tie hair back

Why is the second ionization energy greater than the first ionization energy?

It is more difficult to remove a second electron from an atom.

"Atoms form chemical compounds by combining in fixed ratios."

John Dalton

Suggested that atom structure is related to electric charge.

Michael Faraday

nitrate ion

NO2-

larger atomic radius N or N^-3

N^-3

does not contain a molecule

NaCl

hydroxide ion

OH-

how many protons, neutrons, and electrons are present in ^91 4+ 40 Zr

P-40, N-51 and E-36

sulfate ion

SO4^-2

The meter is the SI base unit for measuring length

True

There are 1,000,000 watts in 1 megawatt.

True

larger ionization energy K or V

V

The closeness of a measurement to its true value is a measure of its

accuracy

A measurement that is very close to the standard accepted value is said to be

accurate

The Law of Conservation of Energy is

always true

factor that contributes to the increase of ionization energy from left to right across the period

an increase in the number of protons

Both homogeneous and heterogeneous mixtures

are blends of two or more substances

An example of a derived quantity is

area

The smallest particle of an element that retains the properties of that element is a(n) ____

atom

The properties of elements reoccur periodically when the elements are arranged in order of increasing

atomic number.

Which of the following numbers is not written correctly in scientific notation? a. 4.7 x 10 b. 6.23 x 10 c. 76.4 x 10 d. 3.56 x 10

c. 76.4 x 10

Burning a piece of toast is an example of a

chemical change

Which of the following elements has the smallest atomic radius?

chlorine