Pre-CHEM 1001 Self-Test

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1 1 of 6 Pre-CHEM 1001 Self-Test Chemistry Mathematics Take these tests on your own. You may use chemistry textbooks/notes and a calculator. You will grade your own answers. Chemistry Section (30 questions): Question #1. Which of the following chemical species is an ion? a) He b) I 3 - c) H S 2 d) Br 2 Question #2. Which of the following chemical species is a compound? a) He b) I 3 - c) H S 2 d) Br 2 Question #3. Carbon-14 has an atomic number of 6 and a mass number of 14. This implies that: a) Carbon-14 has 6 neutrons and 6 protons b) Carbon-14 has 14 neutrons and 6 protons c) Carbon-14 has 8 neutrons and 6 protons d) Carbon-14 has 6 neutrons and 8 protons Question #4. Which of the following atoms is the most electronegative? a) Si b) P c) O d) F Question #5. Among the following elements, assign them to the appropriate families of alkali metals, alkali earth metals, halogens, noble gases, pnictogens, chalcogens, transition metals, lanthanides: element sodium: nitrogen: oxygen: magnesium: barium: phosphorus: neon: rhodium: cerium: fluorine: family Question #6. In every Periodic Table, even the most basic, one can find two numbers associated with each type of element. For example, for zinc (Zn) those numbers are 30 and Explain what these numbers represent. Give units if the numbers have units. Question #7. 55 Fe is a radioactive isotope of iron that can be used to trace the movement of iron in biological systems. In biological experiments it is often added to a system as the +2 or +3 cation. How many protons, electrons and neutrons does the +2 cation of this isotope of iron ( 55 Fe 2+ ) have (the atomic number of iron is 26)? Question #8. The correct formula for nitric acid is: a) HNO 4 b) H 2 NO 3 c) HNO 2 d) HNO 3 e) H 2 NO Question #9. What is the molecular weight of H 2 O? a) g b) 18.0 g c) 32.0 g d) 2.0 g e) 34.0 g

2 2 of 6 Question #10. Vanillin gives vanilla its pleasing smell.the formula for vanillin is C 8 H 8 O 3. How many moles of carbon are present in 2.75 grams of vanillin? a) mole b) mole c) mole d) mole e) mole Question #11. One gram of alum, KAl(SO 4 ) 2 12H 2 O, contains 1.3x10 21 Al atoms. How many oxygen atoms are contained in 1.0 g alum? a) 1.3x10 21 b) 2.6x10 22 c) 1.6x10 22 d) 1.0x10 22 e) 2.1x10 22 Question #12. According to the following reacton, how many moles of water are formed out of a reactive mixture of 8 moles of H 2 and 2 moles of O 2? H 2 + 1/2 O 2 -> H 2 O a) 8 moles b) 2 moles c) 4 moles d) 1 mole Question #13. How many moles of oxygen (O 2 ) are needed to produce 12 moles of carbon dioxide (CO 2 ) in the following reaction: C 4 H 8 + 6O 2 -> 4 CO 2 + 4H 2 O a) 18 moles b) 6 moles c) 3 moles d) 2 moles Question #14. Which of the choices completes this chemical equation correctly? Fe(OH) 3 -> Fe 3+ +? a) (OH) 3 3- b) 3 OH - c) 3 OH + d) 3 OH 3- Question #15. If 12.0 g of PCl 5 reacts completely with water in the balanced chemical reaction below, how many grams of HCl will be produced? PCl 5 + 4H 2 O -> H 3 PO 4 + 5HCl a) 10.5 g b) 2.10 g c) g d) g e) g Question #16. Ammonia (NH ) is produced commercially by a very costly procedure in which nitrogen gas (N ) and hydrogen gas (H ) are combined at very high temperatures and pressures. If x 10 3 g of nitrogen gas and x 10 3 grams of hydrogen gas are reacted in this process, how many grams of NH will be 3 produced? The unbalanced chemical reaction for this process is: N + H -> NH a) 1.88 x 10 3 g b) 2.82 x 10 3 g c) 2.07 x 10 4 g d) 1.12 x 10 4 g e) 5.62 x 10 3 g Question #17. When the equation below is properly balanced, what is the coefficient for S? 8 Cr + S -> Cr S a) 1 b) 2 c) 3 d) 4 e) none of the above Question #18. Balance the chemical equation for the combustion of propane:

3 3 of 6 C 3 H 8 + xo 2 -> yco 2 + 4H 2 O a) x=3, y=5 b) x=5, y=3 c) x=3, y=3 d) x=5, y=5 Question #19. A 4.25 g portion of sodium chloride was dissolved to make up a ml solution. Calculate the mass concentration of sodium chloride in mg/ml. a) 17 mg/ml b) 4.25 mg/ml c) 1060 mg/ml d) 4250 mg/ml e) mg/ml Question #20. If 1.0 L of a 0.50 M NaCl solution is diluted to 2.5x10 3 ml, what is the molarity of the resulting solution? a) 0.40 M b) 2.0x10-4 M c) 4.0x10-3 M d) 0.20 M e) M Question #21. A sample weighed g and it was found to contain 287 mg of sodium bromide. Calculate the weight percent of sodium bromide in the sample. a) % b) 36.4 % c) 57.3 % d) % Question # g of a liquid that has a density of 2.0 g/ml needs to be measured out in a graduated cylinder. What volume of liquid should be measured? a) 2 L b) 20.0 ml c) 200 ml d) 5.0 ml e) 10.0 ml Question #23. The density of water at 22 C is g/ml. Calculate the volume of g of water. a) ml b) ml c) ml d) 22.0 ml Question #24. What is the mass of one mole of calcium phosphate (Ca 3 (PO 4 ) 2 )? a) 183 g b) 215 g c) 278 g d) 310 g Question #25. An antacid tablet containing 0.50 g of NaHCO 3 is dissolved in 250 ml of water. What is the molar concentration of NaHCO 3 in the solution? a) M b) 4.1 M c) M d) M e) M Question #26. How many ml of 0.250M H 2 SO 4 is required to completely react with 25.0 ml of M NaOH? a) 150 ml b) 50.0 ml c) 300. ml d) 75.0 ml e) none of the above Question #27. A ml portion of sulfuric acid was neutralized by adding mole of sodium hydroxide. Calculate the molar amount of sulfuric acid previously in the sample. a) mole b) mole c) 5.0x10 3 mole d) 1.00 mole e) mole Question #28. In the laboratory, you weigh an empty beaker and find it weighs g. You then fill it with 8.0 ml of an unknown liquid, and weigh it again. It now weighs g. What is the density (mass/volume) of the liquid? a) 9.5 g/ml b) 6.2 g/ml c) 5.0 g/ml

4 4 of 6 d) 1.2 g/ml Question #29. One mole of K Cr O has a mass of 294 g. You need to prepare 2.00 L of a solution that contains mol/l of K Cr O. How many grams of K Cr O do you need? a) 29.4 g b) 48.2 g c) 58.8 g d) 588 g Question #30. Assume that you are a physician administering a drug in a solution containing 5.0 mg drug/l solution. If the recommended dosage of the drug is 3.5x10-6 g per kg of body weight, what volume of solution would you prescribe daily for a 150 lb patient (1 lb = 454 g)? Answers top a) 48 ml b) 53 ml c) 86 ml d) 23 ml e) 97 ml top Math Section (20 questions): Question #1. The cost of oranges is $0.28 each. Calculate the number of oranges one can buy with $5.00 and what is the change? Question #2. Jake bought 1.46 kg of beef for $ How much would he have to pay for 2.62 kg? Question #3. A basket, which weighs 23 ounces, contains 8 chicken eggs, 10 quail eggs, and 3 goose eggs. Chicken eggs weigh 1.4 ounces each, quail eggs weigh 0.4 ounces each, and goose eggs weigh 2.1 ounces each. 3.1 What percent of the eggs are chicken eggs? a) 25% b) 35% c) 38% d) 62% 3.2 What is the average (mean) weight of the eggs in the basket, in ounces? a) 1.40 ounces b) 1.02 ounces c) 21.5 ounces d) 1.30 ounces 3.3 What is the total weight of the basket and its contents? a) 21.5 ounces b) 23.0 ounces c) 26.9 ounces d) 44.5 ounces Question #4. You are driving on the freeway at 65 kilometers per hour, and you take your eyes off of the road for 1 second. How many meters do you travel in that time? a) 108 m b) 1.08 m c) 180 m d) 18 m Question #5. How many cubic nanometers are there in 6.8 x ml (1 nm = 1 x 10-9 m and 1 cm 3 = 1 ml)? a) 6.8 x 10-1 nm 3 b) 6.8 x nm 3 c) 6.8 x nm 3 d) 6.8 x nm 3 Question #6. How many of the numbers below have 5 significant figures? x a) 0 b) 1 c) 2 d) 3 e) 4 Question # x 10-3 can also be written as: a) 1.97

5 5 of 6 b) c) d) Question # x 10-5 can also be written as: a) x10-6 b) x 10-4 c) x 10-6 d) Question #9. Given: a = bc, express b in terms of a and c. a) b = c/a b) b = a - c c) b = a/c d) b = c - a Question #10. Solve for n and express it to the nearest whole number: 1/n - 1/5 = a) 3 b) -15 c) 2 d) 6 Question #11. Solve for n and express it to the nearest whole number: 1/2 2-1/n 2 = a) 1 b) 3 c) 5 d) 7 Question #12. Calculate the value of the expression: - R(a -b) a = 3, b = -2, R = 0.58 a) b) 2.9 c) -2.9 d) 0.58 Question #13. Factorize: a 2 b - ab 2 : a) ab(a-b) b) a(ab-b) c) ab(b-a) d) b(ab-b) Question #14. what is x if -log 10 x = 7? a) 10 7 b) -7 c) 10-7 d) 7 Question #15. given k = Ae (-b/t) express T in terms of ln(k/a) and b. a) T = ln(k/a) + b b) T = A/k -b c) T = b/(lnk - lna) d) T = - b/(ln(k/a)) Question #16. Which one of the following equalities is not equivalent to: a/b = c/d (a,b,c,d are real non-zero numbers) a) ad = bc b) d/c = b/a c) a = b x c/d d) (ab)/(cd) = 1 Question #17. Reduce the following expression to a simple fraction: 1/3-1/5 a) -2/15 b) 8/15 c) -8/15

6 6 of 6 d) 2/15 Question #18. Give the answer to the preceding problem in decimals (to the nearest ). a) b) c) d) Question #19. Solve for y the following equation: ax 2 + bx = x - y a) y = 1 - ax + b b) y = x -ax 2 -bx c) y = 1 - b - ax d) y = ax + b -1 Question #20. Data was collected on an experiment that relates "Stuff" to "Blips". Estimate the amount of Stuff you would have if you had 20 Blips? a) 0 b) 10 c) 20 d) 30 e) 40 Answers top

Chemistry 400: General Chemistry Sacramento City College HW#1: Review to Begin Chemistry 400. Review of Chapter 1

Chemistry 400: General Chemistry Sacramento City College HW#1: Review to Begin Chemistry 400 Review of Chapter 1 1) Identify a liquid. A) definite volume and definite shape B) definite volume and no definite