General Chemistry
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Determine the number of significant figures in the following: 0.00650 m.
Determine the number of significant figures in the measurement 12 lb. 4 oz.
Identify the statements that use exact numbers.
(a) The height of the Eiffel Tower from base to tip is 330 m.
(b) 1 inch = 2.54 cm
(c) The current world record for the 100-meter dash is 9.58 seconds set by Jamaica's Usain Bolt in 2009.
(d) 1 US liquid quart = 32 US fluid ounce
Write the given in standard exponential notation rounded off to two significant figures-0.00000092347
Write the given in standard exponential notation rounded off to two significant figures
20342389.54
True or false. If false, correct the statement.
There are more significant figures in 0.088 than in 0.00088
Does the following statement have proper use of significant figures?
The 67th issue of the journal was read by 9,832,456 people.
How many significant figures are in 3.46x104 cm2?
Is the weight of a bottled beer an exact number?
For the following, round to two significant figures
a. 32,324
b. 2.0534x105
c. 453477.23400
d. 0.000000000000934
Determine the number of significant figures in 180000 gal
Determine the number of significant figures in 6.92300x103 yd
Determine whether the number is exact or not exact. Note that the number of significant figures of exact numbers is unlimited.
e (Euler's number) = 2.72
1 ton = 2000 lbs
Express each number in three significant figures
a. 0.00038475
b. 2.9983345
c. 1.78239x105
d. 89,289.35
89,374 when expressed in 2 significant figures, is
0.0892300x10-2 has _ significant figures.
Select the exact numbers from the following:
(a) the mass of a black ballpen
(b) the average height of buildings around the park
(c) the number of liters in a cubic feet of water
(d) the number of employee in an office
(e) the mass of a soda can
Precision is the measure of which of the following?
True or False: A decrease in the number of significant figures results in an increase in the level of certainty in the measurement.
Determine the number of significant figures in the following scientific notation: 2.71×105.
Round the given number to three significant figures using exponential notation: 9,147,593 km2.
Identify the number of significant figures in 0.00678 kg.
Identify the exact numbers:
i) the number of pints to a gallonii) the mass of a rockiii) the number of chapters in a noveliv) the mass of a ream of A4 paper
In an experiment, you use an uncalibrated mass balance to determine the mass of a sample five times. You then placed the sample on a calibrated mass balance and determined its mass to be 4.21 g. What can you conclude about the accuracy and precision of the uncalibrated mass balance?
Shown below are a 10 mL graduated cylinder and a 5 mL graduated pipette. You are supposed to measure out 3.7 mL of water. Which tool will provide the more accurate measurement?
The three dartboards shown below are produced by: Person A an expert using their own darts; Person B only played darts a few times; and Person C a new player of darts. For Person B and Person C to have the same results as those in Person A, which of the following should happen?
The percentage of calcium in a sample of water through a series of experiments. The following data were collected:
Experiment 1: 7.8, 7.3, 7.6 7.4, 7.1Experiment 2: 7.2, 7.5, 7.6, 7.4, 7.3
Determine which experiment is more precise. You can test the precision by calculating the average value of the absolute deviations of each measurement from the mean value.
What is the correct definition for precision?
The percentage of water in a sample is determined by performing the following steps
Step 1: weigh the sample
Step 2: heat the sample to evaporate the water
Step 3: cool sample to room temperature
Step 4: reweigh the remaining sample
This procedure is performed on an unknown hydrate salt. Which condition lowers the measured percentage of water?
The atomic masses for each element in trichloroacetic acid (CCl3CO2H) are Cl = 35.4527 ± 0.0006, C = 12.0106 ± 0.0010, H = 1.00798 ± 0.00014, and O = 15.9990 ±0.0008. Calculate the error for the molar mass of trichloroacetic acid.
The true percentage of lead in a sample is 30.56%. Two students measured the percentage for three determinations. Calculate the average percentage for each set of data.
Student 1: 30.55, 30.54, 30.53
Student 2: 30.53, 30.57, 30.56
State which student had a more accurate measurement based on the average.
The mass of a product from the same chemical reaction has a known weight of 5.20 g. Three groups measured the product. The recorded values are 5.70 g, 5.72 g, and, 5.74 g. The values of the group are ____.
Select the board that best illustrates both accurate and precise measurements with the center of the board representing the "true value".