CH1410 Practice Exam #2 (Katz)

Transcription

1 CH1410 Practice Exam #2 (Katz) Section 1 - Multiple Choice - Write the letter of the BEST CHOICE in the space provided. 1. How are wavelength and frequency of light related? A) Wavelength is one-half of the frequency. B) Wavelength is double the frequency. C) Wavelength increases as frequency increases. D) Wavelength increases as the frequency decreases.. 2. Which form of electromagnetic radiation has the longest wavelength? A) Radio Waves!! B) Microwaves!! C) X-rays!! D) Gamma Rays 3. Which statement below does NOT follow the Bohr Model? A) When energy is absorbed by atoms, the electrons are promoted to higher-energy orbits. B) When an atom emits light, electrons fall from a higher orbit into a lower orbit. C) The energy emitted from a relaxing electron can have any wavelength. D) Electrons exist in specific, quantized orbits. 4. The energy sublevel for the highest energy electrons added to the elements U, Sr, Cl, and Cu are, in the correct order, A) s, p, d, f!!!! B) f,s,p,d. C) p, d,f, s.!!!! D) f,p,d,s. 5. Which subshell letter corresponds to a spherical orbital? A) s!! B) p!! C) d!! D) f 6. What is the electron configuration for Kr?! A) 1s22s22p63s23p43d104s24p6!!!! B) 1s22s22p63s23p64s23d24p6! C) 1s22s22p63s23p64s23d104p6!!!! D) 1s22s22p63s23p24s23d104p6 7. Consider the electron configuration of the ion to determine which ion shown below has an incorrect ionic charge? A) Al3+ B) Se2+ C) Rb+ D) Ba2+ 8. Which one of the following species has the electron configuration of 1s22s 2 2p 6?! 1. Na+ 2. O2-3. F- A) 1 and 2 only!!!! B) 1 and 3 only C) 2 and 3 only!!!! D) 1, 2, and 3

2 9. ) Which of the following atoms is the largest? A) Na!! B) K!! C) Rb!! D) Cs 10. Which of the following atoms has the greatest metallic character? A) Cs!! B) Be!! C) Cu!! D) Ti 11. How many carbon atoms are in the formula Al 2 (CO 3 ) 3? A) 9!! B) 6!! C) 3!! D) How many of each type of atom are there in the formula (NH4)2HPO4? A) N = 2, H = 9, P = 1, O = 4 B) N = 1, H = 5, P = 1, O = 4 C) N = 2, H = 5, P = 1, O = 4 D) N = 2, H = 8, P = 1, O = Which among the following elements does NOT exist as a diatomic molecule in nature? A) hydrogen!! B) nitrogen!! C) fluorine!! D) neon 14 ) Which of the following is a molecular compound? A) barium sulfide!!!!! B) calcium acetate C) potassium hydroxide!!!! D) nitrogen monoxide 15. What is the name of CoS? A) cobalt(ii) sulfide!!!!! B) cobalt sulfide C) cobalt monosulfide!!!! D) cobaltous sulfur 16. ) What is the name of Ca(NO3)2? A) calcium dinitrite!!!!! B) calcium nitrate C) calcium nitride!!!!! D) calcium nitrite 17. What is the correct formula for potassium dichromate? A) K(CrO4)2 B) KCr2O7 C) K2CrO4 D) K2Cr2O7 18. The charge of a vanadium ion in the compound V2O5 is: A) 5+ B) 2+ C) 10+ D) 10-

3 19. What is the name of the molecular compound SO 3? A) sulfur oxide B) sulfur(iv) oxide C) sulfur trioxide D) sulfur tetraoxide 20. What is the proper name for HBr (aq)? A) hydrobromous acid B) hydrousbromic acid C) hydrobromic acid D) bromous acidd) an isotope. 21. What is the formula mass for potassium nitrate? A) amu B) amu C) amu D) amu 22. A compound has a formula mass of amu and is comprised of atoms of sodium and oxygen in a definite ratio. The name of the compound described here is A) sodium monoxide. B) disodium oxide. C) sodium oxide. D) sodium dioxide. 23. A chromium oxide compound contains grams of chromium and 48.0 grams of oxygen. What is the most likely empirical formula of this compound? A) CrO B) CrO2 C) CrO3 D) Cr2O3 24. What is the molecular formula of a compound given the molar mass of the compound is gram and the empirical formula is NH? A) NH B) N2H2 C) N2H6 D) N4H4 25. If you have 1.81 x 1024 atoms of copper, how many moles of copper do you have? A) B) 3.00 C) D) 2.00

4 26. How many atoms of lithium are in 11.8 g of Li? A) 1.35 x 1024 B) 1.70 x 1024 C) 1.02 x 1024 D) 2.22 x How many moles of oxygen are in 3.70 moles of NaClO 4? A) 3.70 B) C) 21.5 D) What is the mass percent of Mg in magnesium chloride (MgCl 2)? A) 12.3 B) 40.7 C) 25.6 D) When the equation, O 2 + C5H12 CO2 + H2O is balanced, the coefficient: of O2 is: A) 3 B) 4 C) 5 D) What are the coefficients for the following reaction when it is properly balanced? Na 3 PO 4 + Ba(NO 3 ) 2 NaNO 3 + Ba 3 (PO 4 ) 2 A) 2, 1, 1, 3 B) 2, 3, 1, 6 C) 2, 3, 6, 1 D) 6, 1, 3, What are the coefficients for the following reaction when it is properly balanced? nitrogen monoxide + carbon monoxide nitrogen + carbon dioxide A) 2, 1, 1, 2 B) 2, 2, 1, 2 C) 2, 2, 2, 1 D) 1, 1, 2, 2 2 NO + 2 CO -----> N2 + 2 CO2 32. Sodium metal reacts with water to form aqueous sodium hydroxide and hydrogen gas. Which equation below best describes the balanced equation for this reaction? A) Na + H2O NaOH (aq) + H (g) B) S + H2O SOH (aq) + H (g) C) Na + H2O NaOH (aq) + H2 (g) D) 2Na + 2H2O 2NaOH (aq) + H2 (g)

5 Section 2 - Answer the following computational questions using the information provided. You must show a plan for your calculations, along with the conversion factors involved for full credit. Write your answer in the box provided. 1. How many atoms of potassium are contained in 3.00 mol of K3PO4? (Avogadro s number = x ) 3.00 mol K3PO4 X 3 mol K atoms X x K atoms = 5.42 x K atoms 1 mol K3PO4 1 mol K atoms 2. How many moles of calcium phosphate are in g of Ca 3 (PO 4 ) 2? (atomic weights: Ca, 40.08; P, 30.97; O, 16.00) Molar Mass Calculation: 3 x = x = x = g/mol Ca3(PO4)2 1 mol Ca3(PO4)2 X g Ca3(PO4)2 = mol Ca3(PO4)2

6 3. How many moles of carbon are contained in g of Pb(CO 3 ) 2? (atomic weights: Pb, 207.2; C, 12.01; O, 16.00) Molar Mass Calculation: 1 x = x = x = g/mol g Pb(CO3)2 1 mol Pb(CO3)2 2 mol C X X = mol C g Pb(CO3)2 1 mol Pb(CO3)2 4. How many grams of sodium are contained in g of NaHCO 3 (molar mass = 84.01)?!!!! g NaHCO3 1 mol NaHCO3 X X _1 mol Na X g Na = g Na g NaHCO3 1 mol NaHCO3 1 mol Na