Vocabulary
This word is used to describe how close our measurements are to one another.
precision
A ruler used to measure a penny has markings every 1mm. What is the correct measurement of the size of the penny reported for this ruler?
A. 19mm B. 19.02mm C. 19.1mm
C. 19.1mm
0,1,2,3
Calculate the number of photons in a 1.75mJ laser pulse which has a wavelength of 2.10micrometers.
1.85x10^6 photons
This experiment predicted alpha particles might deflect slightly, but the even-spread charge would allow them to pass through.
A house has an area of 195m^2. What is its area in cm^2?
1.95x10^6 cm^2
An l value of 2 indicates which orbital?
d
An electron drops from a igher energy level to n=2, emitting a photon w/wavelength 410nm. Find the initial E level.
n initial =6
This type of property is intensive (it doesn't depend on the quantity of the sample) and has units of mass/unit volume.
Density
How many copper atoms are there in 3.56 grams of Cu?
3.56g Cu x (1mol/63.55g) x (6.022x10^23 atoms/1mol) = 3.37x10^22 atoms of Cu
This is the volume in an atom that encompasses 90% of the probability of finding an electron.
An orbital
Mathematically, why does energy increase as frequency increases across the electromagnetic spectrum and decreases as wavelength increases? HINT: Just explain the equations relating frequency and wavelength.
E=hc/w=hv
This law is exemplified when two elements combine and form two different compounds, the masses of element B in either compound that combines with 1 gram of element A can be expressed as a ratio of whole numbers.
Law of Multiple Proportions
Find the mass in pounds of 1.00m^3 of corn syrup (density=1.38g/cm^3). HINT: 1kg=2.02462lbs
1.00m^3 x (100cm/m)^3 x (1.38g/cm^3) x (1kg/1000g) x (2.0246lbs/1kg)= 3.04x10^3 lbs
Ms
When an x-ray photon of wavelength 956pm strikes the surface of a certain metal and it emits an e- with kinetic energy of 9.35x10^4kJ.mol. What is threshold frequency?
7.95x10^16Hz
What is a mole, exactly?
1) the number of atoms in exactly 12g of C-12
2) the amount of material containing 6.022x10^23 particles
The average US farm occupies 435 acres. How many square miles is this? HINT: 1acre=43,560ft^2, 1mile=5280ft
0.680mi^2
Which set of quantum numbers cannot occur together to specify an orbital?
A. n=2, l=1, m(l) =-1
B. n=3, l=2, m(l)=0
C. n=3, l=3, m(l)=2
D. n=4, l=3, m(l)=0
C
The minimum energy required to eject an electron from a certain metal is 235kJ/mol. Find the longest wavelength in nm of electromagnetic radiation that can eject an electron.
509nm