Chemistry Subterm 1 Review Guide
1. Identify the number of significant figures in the following measurements:
a) 43.10°C b) 0.0000520 kg
2. Express the following numbers in scientific notation:
a) 331,000 m b) 0.00000037 m
3. Perform the following metric conversions:
a) 2850 m = km b) 7.56 L = mL
4. Name the following compounds:
a) Br2O7 b) Fe(OH)3
c) N2O5 d) CCl4
e) H3PO4 f) HI
5. Write the formula for the following compounds:
a) tin (IV) oxide b) sulfurous acid
c) hydrobromic acid d) ammonium hydroxide
e) dinitrogen tetroxide e) magnesium phosphate
6. Determine the total number of individual atoms in the following quantities:
a) 317 L of oxygen (O2) at STP (1 mol of gas at STP occupies 22.4 L)
b) 88.2 g ammonium sulfate, (NH4)2SO4
7. Calculate the percent composition of Cu(NO2)2.
8. A compound contains 47.1% potassium, 14.5% carbon, and 38.4% oxygen. The molar mass of the compound is 166.3 grams. What is the molecular formula for the compound?
9. Butane gas, C4H10, burns in air, reacting with oxygen gas to form carbon dioxide and water by the following equation:
C4H10(g) + O2(g) è CO2(g) + H2O(g)
a) Balance the equation
b) How many grams of carbon dioxide will be produced by the combustion of 95.3 grams of butane (in excess oxygen)?
c) If 42.75 L of butane burn completely at STP, how many liters of water vapor will be produced?
10. When an excess of copper metal is reacted with 8.24 grams of silver nitrate, the reaction produces silver metal and copper (II) nitrate, Cu(NO3)2, as shown in the unbalanced equation below:
Cu + AgNO3 è Ag + Cu(NO3)2
a) Balance the equation.
b) What is the theoretical yield of silver in grams? (8.24 grams of silver nitrate are used in the reaction)
c) A chemistry student performed the experiment described in part “b”. She collected 3.71 grams of silver. What was the percent yield?
11. Complete the following table:
Element name / Symbol / Atomic # / Mass # / # of protons / # of electrons / # of neutrons55 Mn
80 / 35 / 36
12. Write the electron configuration for the following elements:
a) Technetium (Tc)
b) Arsenic
13. State the major accomplishment that each of the following scientists is known for.
a) Avogadro
b) Thompson and Millikan
c) Moseley
d) Mendeleev
e) Rutherford
f) Dalton
g) Bohr
14. Determine the number of valence electrons for the following elements:
a) Ne b) Ca c) N
15. Use your reference table and notes to identify the bonds between atoms of the following pairs of elements as ionic, covalent nonpolar, covalent moderately polar, or covalent very polar. SHOW WHY WITH ELECTRONEGATIVITY VALUES WHY YOU CLASSIFY EACH ONE!
a) H and Br
b) Li and O
16. Draw the 3-dimensional structure for, write the name of the shape, and state whether each of the following compounds is polar or nonpolar:
a) PCl3 c) CF4
b) BF3 d) H2S
17. Classify each substance as an element of a compound:
a. water
b. oxygen gas
c. table salt
d. sucrose (type of sugar)
e. gold
18. Which of the following is a chemical change?
a. gasoline boils
b. oxygen is added to gasoline
c. gasoline burns
d. gasoline is poured into a tank.
19. Classify each of the following changes as physical or chemical
a. a puddle is dried by the sun
b. a dark cloth is faded by sunlight
c. bread is toasted
d. soap is mixed with water
20. Which of the following correctly represents an ion pair and the ionic compound the ions form?
a. Ca2+, F-, CaF2
b. Na+, Cl-, NaCl2
c. Ba2+, O2-, Ba2O2
d. Pb4+, O2-, Pb2O4
21. Which set of chemical name and chemical formula for the same compound is correct?
a. magnesium dichromate, MgCrO4
b. lithium nitrate, Li2NO3
c. iron (II) sulfate, FeSO4
d. ammonium phosphate, (NH4)2P
22. Which is the next atomic orbital in the series: 1s22s22p63s2
a. 3f
b. 4s
c. 3p
d. 4d
23. List the 7 nonmetals that exist as diatomic molecules
24. Calculate the moles of selenium atoms in 4.8 x 1025 atoms of selenium
25. What is the percent by mass of glucose, C6H12O6 (calculate the percent of C,H,O separately. The percentages MUST add up to 100%)
26. What is the Empirical Formula of a substance that is 52.2% C, 17.4% H, and 30.4% N by weight?
27. TRUE or FALSE? The limiting reactant in a reaction is the substance that determine the amount of product that can be obtained.
28. A double replacement reaction takes place when aqueous Na2CO3 reacts with aqueous Sn(NO3)2. What would you expect the products to be? (REMEMBER, in a double replacement reaction, just switch the cations in the formulas)
29. How many liters of bromine liquid can be produced when 0.89 L of HBr react with excess O2 at STP? FIRST, balance the equation:
_____ HBr (g) + _____ O2 (g) è ______Br2 (l) + ______H2O (g)
30. Convert -55 °C to K (recall that K = °C + 273)
31. The density of a substance, as measured by a student, is 4.80 g/cm3. The accepted value, as printed in a reliable handbook, is 5.10 g/cm3. Calculate the percent error.
32. Calculate the density of a liquid that has a mass of 14.0 g and a volume of 18.0 cm3.
33. The sum of the protons and neutrons in an atom equals the:
a. atomic number
b. number of electrons
c. atomic mass
d. mass number
34. All atoms of the same element have the same
a. number of protons
b. number of neutrons
c. mass number
d. mass
35. If E is the symbol for an element, which two of the following symbols represents isotopes of the same element?
1) 24 E
12 2) 24 E
13 3) 25 E 4) 25 E
11 12
a. 1 and 2
b. 3 and 4
c. 1 and 4
d. 2 and 3
36. When an atom gains energy, an electron jumps to a higher energy level. The atom is said to be in an EXCITED STATE. This excited state is not stable, so the electron falls down to the ______and emits a ______of energy, which is the light we see.
37. TRUE or FALSE: the ground state of an electron is the lowest possible energy level for a given electron.
38. What is the electron configuration for Fluorine?
Match the following:
Column A / Column B39. ion / a. half the distance between the nuclei of two atoms of the same element when the atoms are joined
40. ionization energy / b. a negatively charged ion
41. electronegativity / c. the energy required to remove an electron from an atom in its gaseous state
42. atomic radius / d. an atom or group of atoms that has a positive or negative charge
43. cation / e. a positively charged ion
44. anion / f. the ability of an atom of an element to attract electrons when the atom is in a compound
45. Electronegativity generally (increases or decreases)______from left to right across the periodic table and (increases or decreases) ______from top to bottom in a group on the periodic table?