Chapters 1 & 2 Study Guide, Study notes of Chemistry

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Date: Per:

Chapters 1 & 2

Study Guide

DIRECTIONS: Fill in the blank(s).

1. Matter is anything that has mass & occupies space.
2. The variable manipulated in an experiment by the researcher is called the independent variable.
3. The variable measured by a researcher in an experiment is called the dependent variable.
4. The standard for comparison in an experiment is called the control group.
5. Complete the table:

SI System of Measures

SI Measurement Unit Symbol SI Prefix Symbol Meaning

Length meter m kilo- k 1000

Mass kilogram kg hecto- h 100

Electrical Current ampere A deka- da 10

Amount mole mol deci- d 1/10th

Time second s centi- c 1.100th

Luminous

Intensity

candela cd milli- m 1/1000th

Temperature kelvin K

6. The boiling point of water at sea level is 373 K or 100 °C.
7. The freezing point of water at sea level is 273 K or 0 °C.
8. The point at which matter stops moving is called absolute zero. It is equal to 0 K or − 273 °C.
9. Convert the following: a. 300. K to °C 27 °C b. 35 .0 °C to K 308 K c. 8 2 °C to K 355 K
10. Contrast accuracy and precision: Accuracy = true compared to a known measure / Precision = ability to reproduce the same measurement repeatedly
11. List the five steps of the scientific method. i. observation ii. question iii. hypothesis iv. experiment v. conclusions
12. Convert the following: a. 156.3 mL to 0. 1563 L c. 0.3461 km to 3461 dm e. 9.15 m to 9150 mm b. 0.0031 kg to 3.1 g d. 34 223 m to 34.233 km f. 0.331 mL to 0.00331 dL
13. How many significant digits are present in each of the following? a. 0.0031mL 2 b. 3.400 N 4 c. 2300 dm 2 d. 0.722 m 3 e. 707.12 km 5 f. 230. L 3

Date: Per:

Chapters 1 & 2

Study Guide

14. Write the following in scientific notation: a. 0.00031 3.1 x 10-^4 b. 3400000 3.4 x 10^6 c. 2300 2.3 x 10^3 d. 0.00 47600 4.7600 x 10−^3
15. Write the following in standard (expanded) notation: a. 3.12 x 10^6 b. 5.201 x 10^7 c. 7.6 x 10−^5 0. d. 3.100 x 10^7 Can’t really be done
16. A physical property is one which does not change the identity of a sample of matter as it is observed and includes such examples as: melting point, boiling point, density, color, odor. A property observed as a substance is undergoes permanent changes into another substance is called a chemical change property and includes such examples as: rusting, burning, rotting, cooking. This second type of property is observed during a chemical change.
17. Fill in the table below. State of Matter Description Definite Shape Definite Volume Indefinite Shape Indefinite Volume Solid Slow moving particles held in rigid structure. X X Gas Particles moving separately with space between them. X X Liquid Particles sliding past one another closely. X X Plasma Superheated gas in which particles become charged. X X
18. Label each change as being either physical (P) or chemical (C). a. Breaking glass P b. Condensing water P c. Lighting a match C d. Burning gasoline C e. Melting metal P f. Freezing water P g. Boiling water P h. Heating plastic P i. Cooking a steak C
19. Define “element”: smallest part of matter with unique chemical and physical properties a. Give three examples of elemental formulas: Mg, Au, Li b. Give two examples of polyatomic elemental formulas: H 2 , O 2
20. Define “compound”: a unit of matter with fixed proportions of certain elements a. Give two examples of compound formulas: NaCl, CO 2
21. Label each of the following as either an atomic formula (formula of an element) (A) or a compound formula (C). a. MgO C b. He A c. CO C d. NO C e. Co A f. No A g. H 2 O C h. Sn 3 N 4 C i. Sn A

Date: Per:

Chapters 1 & 2

Study Guide

DIRECTIONS: Complete the calculations in the space provided.

27. If a 37.50 g weight is placed in a graduated cylinder with 41.0 mL of water and the water level goes up to 44.3 mL, what is the density of the weight? m = 37.50 g Vinitial = 41.0 mL Vfinal = 44.3 mL Volume of object = 44.3^ mL^ –^ 41.0 mL = 3.3 mL Density of object = mass / volume = 37.50 g / 3.3 mL = 1 1 .363636 g/mL ( 2 sig figs because 3.3 mL only has 2 sig figs) 11 g / mL
28. A 3.75 g object with a density of 2.380 g/mL is placed in a graduated cylinder containing 20.50 mL of water. What is the final volume of the graduated cylinder after the object has sunk? m = 37.5 g D = m/v D = 2.380 g/mL V = mD V = 37.5 g x 2.380 g/mL = 10. 6 125 mL (3 sig figs because 37.5 g has 3 sig figs) Final volume in cylinder = 20.50 mL + 10. 6 1 mL = 31. 1 1 mL (Round to tenths because 10.61 ml should have been rounded to tenths place. 31.1 mL
29. A graduated cylinder contains 30.00 mL of water. An object with a volume of 12.00 cm^3 is placed in the graduated cylinder and floats with only a portion of the object beneath the surface. If the water level in the graduated cylinder has increased to 34.50 mL, what is the density of the object? A floating object displaces an equal mass of water. If the water level has increased by 4.50 mL (34.50 mL – 30.00 mL = 4.5 0 mL) and water has a density of 1 g/mL, then the object has a mass of 4.50 g (Round to hundredths since both measures are rounded to hundredths). D = m/v = 4.50 g / 12.00 cm^3 = 0. 375 g/ cm^3 (Round to 3 sig figs since 4.50 g has only 3 sig figs) 0.375 g / cm^3
30. A calculation indicates that a reaction should produce 1.87 g of product. After carrying out the experiment, only 1.650 g of product have been collected. Calculate the percent error. Percent error = experimental – accepted x 100 accepted Experimental = 1.650 g Accepted = 1.87 g Percent error = 1.650 g – 1.87 g x 100 ^ − 0.2 2 g x 100 = − 11 .7 647 % 1.87 g 1.87 g 12%