Conversions
What is the system we use called?
SI units
Trailing zeros are always significant...is there an exception?
T or F?
What are the units for density?
g/mL or g/cm^3
What is the conversion factor to go from Celsius to Fahrenheit?
What are the two types of Mixtures?
Homogenous and heterogenous
Set up dimensional analysis
# units of you have x _______= #units you want
units you want/units you have
How many sig figs 0.00235
3!
How would you find the volume using the density formula?
D=m/v
V=m/D
What is 43.8 degrees celsius in kelvin?
316.95 K
How many sig figs?
Which one is a chemical change?
Solid->liquid
Tarnish/rust
Melting butter
Dissolving salt in water
Tarnish/rust
other ones: burning, rotting, and cooking
Milli
Write 5.08x10^4 in decimal form
50,800
Mercury metal is poured into a graduated cylinder that holds exactly 22.5 mL. The mercury used to fill the cylinder weighs 306.0 g. From this information, calculate the density of mercury
d = 306.0 g / 22.5 mL
d = 13.6 g/mL
Analysis of 4.200 g of vitamin C yields 1.720 g of carbon, 0.190 g of hydrogen, and 2.290 g of oxygen. Calculate the mass percentage of each element in the compound
40.95%
4.52%
54.52%
What is the difference between a compound and an element?
compound-can be broken down more
element=purest form can not be broken down
How many cg are in 2.49 x 10^3 mg?
249 cg
( 1 g / 1000 mg)(100 cg / 1 g) = 249 cg or 2.49 x 10^2 cg
12.5849 mg + 2.4 mg=
*correct sig figs!
246m x1.5m
15.0 mg
370 m2
Find the mass of 250.0 mL of benzene. The density of benzene is 0.8765 g/mL.
d = g / mL
g = (d) (mL)
g = (0.8765 g/mL) (250.0 mL) = 219.1 g
Determine energy required in kilojoules when cooling 456.2 grams of water at 89.2 C to a temperature of 5.9 C?
Delta H=-159 kJ
Which one is a metal? Which one is the most electronegative?
-Nitrogen
-Fluorine
-Argon
-Strontium
-Phosphorous
Strontium---Fluorine
How many km are in 5.00 miles?
1760yds/mile
3ft/yd
5.00 mile(1760 yds / 1 mile)(3 ft / 1 yd)(12 in / 1 ft)(2.54 cm / 1 in)(1 m / 100cm)(1 km / 1000m ) =
8.05 km
3.85 x 10-18 / 7.35 x 10-36=
(5.55 x 1015) (8.88 x 1018) =
5.24 x 10^17
4.93 x 10^34
28.5 g of iron shot is added to a graduated cylinder containing 45.50 mL of water. The water level rises to the 49.10 mL mark, From this information, calculate the density of iron.
vol of iron shot = 49.10 mL - 45.50 mL = 3.60 mL
d = 28.5 g / 3.60 mL
d = 7.92 g/mL
A compound with 45 protons 44 neutrons and 43 electrons has what charge?
-2
Which element would have physical and chemical properties similar to chlorine? Write the name of the element.
A. Ar
B. Br
C. S
D. O
Bromine! Same group aka column so will have similar properties