Memorize: Understand: Know how to:

Transcription

1 NAME: CLASS PERIOD: REVIEW FOR HONORS CHEMISTRY SEMESTER 1 EXAM Memorize: Understand: Know how to: 1 SI units for different measurements (length, volume, number, mass, temperature, density) Definition of homogeneous, heterogeneous, element, pure substance, and mixture Significant figures for numbers and in calculations Characteristics of a solid, liquid, gas Difference between pure substance and mixtures Identify matter as element, compound, pure substance, mixture 2 Signs of a chemical change Laws of Conservation of Matter and Energy Difference between endothermic and exothermic reactions How to set up and solve mathematical equations that include unit conversions Difference between accuracy and precision The difference between chemical and physical properties and physical and chemical change Do unit conversions Calculate density Write numbers in correct scientific notation and significant figures Classify changes as physical or chemical 3 Mass number, atomic number, atomic mass, molar mass, mole Avogadro s number Key scientists and their contributions (Dalton, Rutherford, Thompson, Bohr, Mendeleev, Moseley) Aufbau principle Letters for orbitals and number of electrons per orbital The experiments leading to the modern understanding of atomic structure The relative mass and volume of each subatomic particle and the space it occupies What an electron orbital is and the significance knowing electron configuration How to get from g->mol and mol->g Match scientist and their contribution to the model of the atom or the arrangement in periodic table Convert between grams and moles, moles and grams, moles and number of particles (using Avogadro s number) Write electron configurations for elements in both standard and noble gas forms

2 4 Element names and symbols (at a minimum, elements through #20 (Ca) plus Fe, Ni, Cu, Zn, Se, Br, Rb, Sr, Ag, Sn, I, Cs, Ba) What parts of the periodic table have metals, nonmetals and metalloids Names and location for groups of elements in the periodic table (alkali metals, alkaline earth metals, transition metals, halogens, noble gasses) Define isotope and allotrope How periodic table is organized (groups and periods) How elements in a group and period are similar or different Definitions and trends across the periodic table: ionization energy, electron affinity, electronegativity, and atomic/ionic radius The concept of energy levels and electron shielding and how they affect trends The origin of elements and the meaning of transmutation Compare chemical properties between elements based on trends in the periodic table Identify the ending electron configuration of an element based on the group it is in (Ex: ns 1 = Alkali metals) 2

3 s 5 & 6 What kind of elements form ionic and covalent bonds Naming rules for ionic and covalent compounds (including prefixes for covalent compounds) Names, formulas and charges of polyatomic ions (ammonium, acetate, hydroxide, nitrate, carbonate, sulfate, phosphate) Key molecular shape names (linear, tetrahedral, trigonal planar, bent, trigonal pyramidal) Meaning of empirical formula, molecular formula, molecule, formula unit Definition of resonance structure What happens with electrons in ionic bonding (transfer) and covalent bonding (sharing) Polar vs. nonpolar bonds, polar vs. nonpolar molecules What is meant by a dipole and partial charges The meaning of subscripts in chemical formulas Difference between cation and anion, which elements form them Significance of Roman numerals in compound names for transition metals Ionization energy, electron affinity, lattice energy Which elements go in the middle and outside of a Lewis structure The concept of single, double and triple bonds and how many electron pairs are shared between the atoms How unbonded electron pairs on the central atom influence molecular shape (Ex: NH 3 or H 2 O) The relationship between empirical and molecular formulas Predict ion charge for elements based on their group in the periodic table Determine if a molecule is polar or nonpolar from molecular shape Indicate a partial charge or dipole in a bond or molecule. Write names or formulas for ionic and covalent compounds Determine number of ions needed to balance charges in a compound Draw Lewis structures for molecules and polyatomic ions Include brackets and charge or resonance structures as required Use valence shell electron pair repulsion (VSEPR) theory to predict molecular shapes Calculate molar mass of an atom, compound, or molecule Determine percent composition as well as empirical and molecular formulas 3

4 7 Avogadro s Number Mole Molar mass Average atomic mass Percentage composition Empirical formula Molecular formula The significance of Avogadro s number The significance of a chemical formula in determining the composition of the compound Use the chemical formula to calculate the percentage composition of elements in a compound. Determine the molecular formula from the empirical formula. Determine the empirical formula from percent composition. Determine the molar mass of a compound. Calculate average atomic mass. Review Questions. Work these on a separate sheet of paper to give yourself enough room! 1. Rewrite the following with 1, 2, and 3 significant figures in both regular and scientific notation: For each formula, write the name. For each name, write the formula. Identify each compound as covalent or ionic. a. Na 2 SO 4 f. Fe(NO 3 ) 3 b. CO g. Ammonium hydroxide c. K 3 PO 4 h. Potassium chloride d. LiF i. Diphosphorous pentoxide e. SiO 2 j. Calcium carbonate 3. Write the formula and charge for: a. Sulfate b. Nitrate c. Phosphate d. Carbonate e. Hydroxide f. Ammonium 4. Write the full and noble gas electron configurations for the following: Zn, K, Br 5. To which group would an element with a valence electron configuration ns 2 np 3 belong? n represents the period (row) for that element. 6. How can you tell what kind of ion an element will form and what its charge will be by looking at the periodic table? (Example: Li L +, P P 3- ) 4

5 Name: 7. What kind of elements bond together for form an ionic compound? A covalent compound? 8. Draw Lewis dot diagrams for single atoms of oxygen, magnesium and argon. 9. Draw Lewis structures and predict the shapes of the following. Show resonance structures where required. a. Ammonium e. Sulfate b. Nitrate f. Phosphate c. Hydroxide g. Carbon dioxide d. Nitrogen gas (N 2 ) h. Water 10. Are the following molecules polar or nonpolar? Explain your reasoning. a. CH 4 d. CO b. CO 2 e. HCl c. NH 3 f. H 2 O 11. What is a multiple bond? What is the greatest number of electrons that can be shared between two atoms? 12. Convert the following: a mol C to grams C b g C to atoms C c mol C to atoms C d x atoms C to grams C 13. Why are ionic substances solid at room temp but covalent substances are often liquid or gas at room temp? 14. How are chemical and physical changes different? 15. What are the two types of mixtures? How do they differ? 16. Find the % composition, empirical formula, molecular formula or molar mass of the whole compound as required: Molecular formula Empirical formula % composition Molar mass C 6 H 12 O % Fe, 22.3% O 71.8 g/mol CH 2 O 90.0 g/mol 17. What are the atomic number and mass number for: C-12 C-14 U-235 U-238 5