Show:
Metric Conversions
Chemistry Word Problems
Scientific Notation
Atomic Structure
Isotopes
100
Which is larger? 1 cg or 1 mg?
What is 1 cg?
100
If the melting point of Ag (silver) is 962 degrees C, what is this temperature in K (Kelvin)?
What is 1235 K
100
Calculate 5.3 x 10^4 + 1.3 x 10^4
What is 6.6 x 10^4
100
What subatomic particles make up the nucleus of any atom?
What are protons and neutrons?
100
Carbon-12 is the most predominant form of carbon found in nature (98.89%) and has an atomic mass unit (amu) of 12. There is a small percentage of Carbon-13 also found in nature (1.11%). How does this affect the atomic mass of carbon overall?
What is the atomic mass of all carbon found in nature is slightly higher than 12 amu (it's 12.011)
200
Which is larger? 1 um or 1 nm?
What is 1 um?
200
What is the speed of light in km/hr if the known speed of light is 3.00 x 10^10 cm/s? (Don't forget sig figs!)
What is 1.08 x 10^9 km/hr?
200
Calculate 10^4 x 10^-3 x 10^6
What is 10^7
200
What defines the identity of any element?
What is the number of protons (or atomic number)?
200
S (sulfur) is found in nature as 4 different isotopes (S-32, S-33, S-34 and S-36). If the periodic table lists the atomic mass of sulfur as 32.064, which form of sulfur is the most predominant in nature?
What is S-32 (it makes of 95% of sulfur in nature).
300
Convert and Express in Scientific Notation: 0.764 km ---> ? cm
What is 7.64 x 10^4 cm
300
A cheetah has been clocked at 112 km/hr over a 100 m distance. What is her speed in m/s? (Don't forget sig figs!)
What is 31 m/s
300
How many significant digits are in this number? 3.4506 x 10^6
What is 5?
300
How many neutrons are in the element Gallium, given the following: atomic number = 31 atomic mass = 70
What is 39?
300
The atomic mass of Zn (zinc) is listed in the periodic table as 65.38. There is no Zn atom with this mass. Explain.
What is the existence of various isotopes of zinc means that the average atomic mass will not equal a particular Zn atom. (NOTE: Zn exists in 5 isotopes in nature, the most abundant form is Zn-64 at 48.89%)
400
Convert and express in scientific notation: 14.8 g ---> ? ug
What is 1.48 x 10^7 ug
400
A weather balloon is inflated to a volume of 2.2 x 10^3 L with 37.4 g of He (helium). What is the density of He in g/L? (answer with correct sig figs and in scientific notation)
What is 1.7 x 10^-2 g/L
400
Calculate 7.2 x 10^4 / 1.8 x 10^3 (don't forget to use the proper number of sig figs)
What is 4.0 x 10^1
400
List the number of protons, neutrons and electrons for the following atom of selenium: 78 34 Se
What is 34, 44, 34?
400
One postulate of Dalton's atomic theory is that "Atoms of the same element are identical", how does our current knowledge of the atom alter this postulate?
What is the discovery of of isotopes demonstrated that individual elements can exist in different forms
500
Convert and Express in Scientific Notation: 7.5 x 10^4 nm ---> ? km
What is 7.5 x 10^-8 km
500
What is the mass of an Al (aluminum) cube that is 3.0 cm on each edge? (Density of Al = 2.7 g/cm^3) (don't forget sig figs!)
What is 73 g?
500
Calculate: 4.8 x 10^-5 __________ x 6.0 x 10^3 2.0 x 10^-2
What is 1.44 x 10^1
500
Explain how there can be more than 1000 different types of atoms when there are only 118 different elements
What is because most elements exist as multiple isotopes
500
There are 2 naturally occurring isotopes of copper: Cu-63 and Cu-65. The relative abundance and atomic masses are: Cu-63: 69.2% and 62.93 amu Cu-65: 30.8% and 64.93 amu Calculate the average atomic mass of copper
What is 63.5 amu