Chem Lecture Test 1
What is -6 C in F?
-6 x 9/5 = -10.8 -10.8 + 32 = 21.2 F
what are the Sig Figs of the answer to this problem? 9.02 - 18.1496 =
-9.13 3 SF
What is 200 cm in km?
0.002 km
How many mg are in a kg?
1,000,000 mg
What is the average mass in grams of an oxygen atom?
15.9994 x 1.66E-24 = 2.66E-23
Complete and round to correct # of Sig Figs 1. 4.337 + 84.7128 = 2. 19.6 - 8.77 = 3. 19.8 - 8.75 + 11 =
89.05 10.8 22
Define and contract Kinetic and Potential energy.
Kinetic energy = active energy Potential energy = stored energy
What element is Hg?
Mercury
Copper is a reddish-orange color. is this a physical property or a chemical property?
Physical
Using Q=Sm^T Solve: When 23g of magnesium is used 925 cal to go from 6 C to 65 C, what is the specific heat?
S = Q/m^T S = 925 cal/23g x 65-6 S = 0.68 cal/g C
what state of matter has the most kinetic energy?
gas
the periodic table is organized vertically by ____ and horizontally by ____.
groups and periods
What is the difference between kinetic and potential energy?
potential energy is when the object is in a state of rest. Kinetic energy is when the object is in a state of motion.
What two parts of the atom are represented by the atomic number?
protons and electrons
What is sublimation?
solid to gas
What type of substance is a fruit salad? a. Element b. Compound c. Homogeneous Mixture d. Heterogeneous Mixture
Heterogeneous Mixture
On planet Tatooine, the isotopic abundance of Sodium (Na) is different than that on planet Earth. The abundance of Sodium on Tatooine is as follows: Ato. Mass Abundance: 23Na 6.59 amu 60.00% 24Na 7.79 amu 30.00% 25Na 8.43 amu 10.00% Calculate the average atomic mass of a sodium atom (22.99) on Tatooine. How much less is it than the average atomic mass of Sodium on Earth?
23Na: 3.954 24Na: 2.337 25Na: 0.843 All together: 7.134 amu 22.99 amu - 7.134 amu = 15.86 amu more is on Earth
A rattlesnake is 2.44 m. How many cm is the rattlesnake?
244 cm
convert 65 F to K.
65 - 32 = 33 33 x 5 = 165 165/9 = 18.33 18.33 + 273.15 291 K
what is 75.0 miles/hour converted to meter/second? 1 km = 0.621 miles Write the answer in scientific notation using the correct number of sig figs.
75 miles/h x 1 km/0.621 mil x 1000 m/1 km x 1 h/ 3600 = 33.5 m/s 3.35E1 m/s