SIG FIGS
how many sig figs are in the 3.45 m?
3 SFs
a cup of whole milk contains 13 g of carbs, 9.0 g of fat, and 9.0 g of protein. How many kilocalories is this? (round your final answer to tenths place.)
170 kcal
625 mg = _________g?
what is the formula for density?
D = m/v
the heat of fusion
how many sig figs are in 0.0007 g?
1 SF
how many calories are obtained from a pat of butter if it provides 150 J of energy when metabolized?
36 calories
525 mL = __________dL?
5.25 dL
Marie weighs 125 lbs. She has a blood volume of 7.5 qt. If the density of blood is 1.06 g/mL, what is the mass (in grams) of Marie's blood?
7,500 g or 7.5 x 10^3 g
what is the process in which a solid changes directly to a gas?
sublimation
calculate the following with the correct number of sig figs:
27.41 + 611 = ?
638.41 , which rounds to 638.
How many kJ of heat energy can 250.0 g of water initially at 23.0 C absorb before the water boils at 100.0 C?
(hint: specific heat of water is 4.184 J/g C)
80.5 kJ
24,625 mi = _________m?
39,631,000 m
what unit is used for specific gravity?
it is unitless
From point D to E on a heating curve, it is at the boiling point. What state phases are occurring here?
liquid and gas phase
express the following in scientific notation rounded to 2 sig figs:
10,000,000
1.0 x 10^7
what is the specific heat of 30.2 g of a metal that absorbs 225 J of energy and the temperature rises from 32.0 C to 53.0 C?
0.355 J/g C
34.8 C = ________ F?
94.6 F
The mass of a substance is 57.96 g and a volume of 3.00 cm3. Find the density. Based on the density, what element could this substance be? Find the specific gravity of this substance.
D= m/v
D= 57.96g/ 3 cm3 = 19.32 g/cm3 ~ 19.3 g/cm3
Gold has a density of 19.3 g/cm3, Tungsten would also be an acceptable answer (19.25 g/cm3)
Sp. Grav. = 19.3 g/cm3 / 1.000 g/cm3 = 19.3
The temperature at which solid and liquid are in equilibrium is?
the melting point and freezing point
how many sig figs are in 35 apples?
infinite, it is an exact number
what is the difference between kinetic and potential energy?
kinetic: energy of motion
potential: energy stored for use at a later time (aka has the POTENTIAL to be in motion)
25 ft/s= ____________m/min?
46 m/min
A jeweler wants to determine the specific gravity of a gemstone. She weighs the gemstone in air, and it has a mass of 25 grams. She then suspends the gemstone in a container of water and finds that it displaces 5 mL of water. Calculate the specific gravity of the gemstone.
5
on a heating curve, the line plateaus at the melting point. why is this?
the substance absorbs the heat and kinetic energy forms. When the phases change the intermolecular forces break.