Chemistry Midterm

celcius =

(F-32)/1.8

A chemist weighed out 4.4 g of tungsten. Calculate the number of moles of tungsten she weighed out.

0.024 mol

1 J=

1 kg m^2*s^-2

1 Pa=

1 kg*m^-1*s^-2

Farenheit =

1.8C + 32

speed of light

3.00 x 10^8 m/s

Avogadro's number

6.02 x 10^23

Planck's constant

6.626 x 10^-34

electron attachment reaction F + e- --> F

A reaction in which a neutral atom gains an outer electron is called an electron attachment reaction: the amount of energy will always be electron affinity

Ionization reaction Na --> Na + e-

A reaction in which a neutral atom loses an outer electron is called an ionization reaction: the energy will always be the ionization energy thats given.

atomic mass of an element formula

A= m1p1 + m2p2 + ...

C2H3O2-

Acetate

NH4+

Ammonium

Typical metals...

Are solid at room temperature (except mercury). Conduct electricity and heat well. Are malleable (can be bent without breaking). Are usually shiny white or gray. (Two major exceptions are gold and copper, which have a light yellow and light red tint, respectively.) Have a lower first ionization energy. Form cations in ionic compounds. Are only found in positive oxidation states.

bromate

BrO3-

BrO3−

Bromate

kelvin =

C + 273

Acetate

C2H3O2- CH3COO-

Cyanide

CN-

carbonate

CO3 2-

CO32−

Carbonate

ClO3−

Chlorate

CrO_4^2-

Chromate

chlorate

ClO3-

Chromate

CrO4 2-

CN-

Cyanide

Density formula

D=m/v

hydronium

H3O+

OH-

Hydroxide

Iodate

IO3-

A robot spacecraft returned samples from the planetesimal 98765 Aleks, located in the outer Solar System. Mass-spectroscopic analysis produced the following data on the isotopes of ruthenium in these samples: isotope -- mass -- relative abundance ^100Ru -- 99.90 -- 98.6% ^98Ru -- 97.91 -- 1.4% Use these measurements to complete the entry for ruthenium in the Periodic Table that would be used on 98765 Aleks. Be sure your answers have the correct number of significant digits. ___ Ru ___

In general the atomic mass A of an element can be found by multiplying the mass m of each isotope by the natural abundance p of the isotope, and then adding up the results: 44 Ru 99.9

IO3−

Iodate

kinetic energy formula

KE=1/2mv^2

Typical nonmetals...

May be solids, liquids or gases at room temperature. Usually conduct electricity and heat poorly. (Carbon is an important exception.) Are usually brittle (break before bending) in the solid state. Are usually an unreflective white, or brightly colored, in the solid or liquid state. Have a higher first ionization energy. Form anions in ionic compounds. Are found in both positive and negative oxidation states.

Permanganate

MnO4-

ammonium

NH4+

nitrate

NO3-

NO_3-

Nitrate

NO_2-

Nitrite

Peroxide

O2 2-

hydroxide

OH-

phosphate

PO4 3-

MnO4-

Permanganate

O2 2-

Peroxide

PO43-

Phosphate

sulfate

SO4 2-

SO42−

Sulfate

NH3

ammonia

most common oxoanion

ate

number of electrons

atomic number

Atoms or ions get ______ as you go down along a group of the Periodic Table.

bigger

how do you determine n from the sub shell?

by looking at the number: 1s --> n=1 2p --> n=2 4d --> n=4

v=

c/λ c= speed of light λ= wavelength

A chemistry grad student measures the performance Z of the new pump in his lab. The result is: Z=18.8 kPA*mm^3*s^-1 Convert Z to mJ*s^-1

convert kPA to PA convert PA to 1 kg*m^-1*s^-2 convert mm to m convert kg*m^2*s^-2 to J conver J to mJ answer: Z= 0.0188 mJ*s^-1

electromagnetic spectrum

gamma rays, x rays, ultraviolet rays, visible light (VIBGYOR), infrared, microwave, radio ----->wavelength <----- frequency

higher frequency =

higher energy

E=

hv (h = Planck's constant; v = frequency)

oxoanion with 2 less O atoms

hypo-ite

ionic compound

ionic compound is always made from one metal element and one nonmetal element

when electron is on the right side

it absorbs energy

when electron is on the left side

it releases energy

oxoanion with 1 less O atom

ite

Anions are _____ than a neutral atom of the same element.

larger

number of atoms: 1 2 3 4 5 6 7 8 9 10

mono- 1 hexa- 6 di- 2 hepta- 7 tri- 3 octa- 8 tetra- 4 nona- 9 penta- 5 deca- 10

You can always

multiply measurements (g*g = g^2)

the 1s sub shell: n= l= how many states?

n=1 l=0 2 states

the 3p sub shell n= l= how many states?

n=3 l=1 6 states

the 3d sub shell n= l= how many states?

n=3 l=2 10 states

the 4s sub shell n= l= how many states?

n=4 l=0 2 states

the 4p sub shell n= l= how many states?

n=4 l=1 6

the 5p sub shell n= l= how many states?

n=5 l=1 6 states

oxoanion with 1 more O atom

per-ate

for the following sub shells, what does l=? s, p, d, f, g

s=0 p=1 d=2 f=3 g=4

s^3 * s^2 =

s^5

Atoms or ions get ______ as you go from left to right along a period of the Periodic Table.

smaller

Cations are _____ than a neutral atom of the same element.

smaller

Most of the common oxoanions have 3 oxygen atoms, but ________ have 4.

sulfate and phosphate

When you add or subtract measurements,

the only decimal places in the answer that are significant are those that appear in all the measurements.

atomic number on atomic weight on

top bottom

lattice energy increases

up and to the right

A chemistry student needs 70.0g of methyl acetate for an experiment. By consulting the CRC Handbook of Chemistry and Physics, the student discovers that the density of methyl acetate is 0.934 g*cm^-3. Calculate the volume of methyl acetate the student should pour out. Be sure your answer has the correct number of significant digits.

v=m/D answer: 74.9 mL