Scientific Method/Properties of Matter
Classify the following as an observation, hypothesis, or experiment:
A. You notice that there is more traffic between 8 and 9 in the morning
B. There is more traffic between 8 and 9 in the morning because most people start work at 9.
A. Observation
B. Hypothesis
How many significant figures?
A. 45.030 mm
B. 0.00208 cm
C. 0.00001 mL
D. 100. g
A. 5
B. 3
C. 1
D. 3
How many joules are required to raise the temperature of a 35.0 g sample of iron from 25 °C to 35 °C? Iron has a specific heat of 0.450 J/g °C.
q= mcΔT
160 J
Which of the following measurements are NOT equivalent?
A) 25 mg = 0.025 g
B) 183 L = 0.183 kL
C) 150. msec = 0.150 sec
D) 84 cm = 8.4 mm
E) 24 dL = 2.4 L
D. 84 cm = 8.4 mm
Which of the following descriptions of a subatomic particle is correct?
A) A proton has a positive charge and a mass of approximately 1 amu.
B) An electron has a negative charge and a mass of approximately 1 amu.
C) A neutron has no charge and its mass is negligible.
D) A proton has a positive charge and a negligible mass.
E) A neutron has a positive charge and a mass of approximately 1 amu.
A) A proton has a positive charge and a mass of approximately 1 amu.
Which of the following is an example of a homogenous mixture?
A. Sand mixed with oil
B. Salt dissolved in water
C. Table sugar
D. Gasoline mixed with water
E. Ball bearings in a box
B. Salt dissolved in water
Write the following number in correct scientific notation:
0.00452 x 10-2
4.52 x 10-5
A solution has a density of 1.22 g/mL. What volume of the solution has a mass of 48.2 g?
39.5 mL
85°F to K
302 K
Gives the correct numbers of protons, neutrons, and electrons in a neutral atom of 11850Sn?
50 protons, 68 neutrons, 50 electrons
Classify the following as an observation, hypothesis, or experiment:
A. I found a small piece of metal at the beach that is yellow and shiny which makes me think it might be gold
B. Gold is a shiny, yellow metal
C. I scratch a small piece of the metal off and add a drop of acid to determine if it is real or not
A. hypothesis
B. Observation
C. Experiment
Which of the following numbers contains the designated correct number of significant figures?
A. 0.04300 5 significant figures
B. 0.00302 2 significant figures
C. 156000 3 significant figures
D. 1.04 2 significant figures
E. 3.0650 4 significant figures
C. 156000 3 significant figures
Calculate the specific heat capacity of a new alloy if a 15.4 g sample absorbs 393 J when it is heated from 0.0/C to 37.6 /C.
0.679 J/g C
A dose of aspirin of 5.0 mg per kilogram of body weight has been prescribed to reduce the fever of an infant weighing 8.5 pounds. The number of milligrams of aspirin that should be administered is ____.
(1 kg=2.205 lb)
19 mg
4119K
Which of the following is an example of a heterogenous mixture?
A. sand mixed with oil
B. salt dissolved in water
C. air
D. Coffee
E. Vinegar
A. sand mixed with oil
Write the following in scientific notation:
A. 540,000
B. 0.00000033
C. 0.000004003
A. 5.4 x 105
B. 3.3 x 10-7
C.4.003 x 10-6
A nugget of gold with a mass of 521 g is added to 50.0 mL of water. The water level rises to a volume of 77.0 mL. What is the density of the gold?
19.3 g/mL
54.0°C to °F
129.2 °F
Write the Atomic symbol for the following:
A. 26 protons, 31 neutrons, 26 electrons
B. 10 protons, 8 neutrons
C. 37 electrons, 38 neutrons
A. 5726Fe
B.1810Ne
C. 7537Rb
Describe the following as a chemical or physical change:
A. wood burning in a fireplace
B. water freezing
C. digesting a hot dog
D. grinding pepper
A. chemical change
B. physical
C. chemical
D. physical
A. 7.5 g + 2.26 g + 1.311 g + 2 g
B. (43.258 x 9.04 x 1.00005)/14.05
A. 13 g
B. 27.8
A 55 kg block of metal has an original temperature of 15.0°C and 0.45 J/g°C. What will be the final temperature of this metal if 450 J of heat energy are added?
15 °C
If a car travels 23 miles on 1.0 gal of gas, how many liters of gasoline are needed for a 135 km trip?
1 gal= 3.785 L
1 mile= 1.609 km
14 L
Naturally occurring boron (B) consists of two isotopes with a mass of 10 and 11. Boron-10 has an abundance of 18.7% and boron-11 has an abundance of 81.3%. What is the relative atomic mass of Boron?
10.813 amu