midterm review. 1. what is the mass of the solution when 50.0 g of salt is dissolved in 150.0 grams...
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Midterm Review
1. What is the mass of the solution when 50.0 g of salt is dissolved in 150.0 grams of water?
a. 190.0 grams
b. 150.0 grams
c. between 50.0 and 150.0 grams
d. 200.0 grams
e. more than 200.0 grams
200.00 g
2. How many significant digits are in the following measurement?
345000000000 nm
3
3. Read the graduated cylinder below to the appropriate number of significant digits.
67.9 mL
4. Read the ruler below to the appropriate number of significant digits.
30.0 mm
6.50 mL
5. Read the graduated cylinder below to the appropriate number of significant digits.
19 in = ? km1 in= 2.54 cm
0.00048 km
6. Convert the following measurement to the indicated unit using dimensional analysis.
a. 7. Predict which element would be most likely to form an anion and what charge:
a. Pb
b. Cl
c. He
d. Ca
e. Zn
b. Cl 1-
8. A distinct pattern of lines emitted by an excited atom and viewed through a spectroscope is a _______________ spectrum.
Emission
9. Which of the following correctly represents the first ionization energy of Calcium?
Ca(g) Ca+(g) + e-
a. Ca(s) Ca+(s) + e-
b. Ca(g) + e- Ca+(g)
c. Ca(s) + e- Ca+(s)
d. Ca(g) Ca+(g) + e-
e. Ca(g) Ca2+(g) + e-
10. An area of 90% probability for finding an electron is a(n) ______________?
Orbital
11. Which of the following bonds is probably the most polar?
– N–H– O–H– P–H– Se–H– C–H
O–H
12. Light has a wavelength of 470 nm. What is the energy of this light?
E= h [c/ wavelength]
4.2x10x10-19 J
13. A sample of zinc-72 has an initial activity of 2310 counts per minute on a device that measures the level of radioactivity. After 120 hours the activity declined to 457 counts per min. What is the half-life for decay of zinc-72?
457 = 2310 ( .5)n
n= 2.33
120/2.33 = 52 hrs
14. A student in the laboratory determined the density of a substance to be 14.2 g/mL. The accepted value for the density of this substance is 13.87 g/mL. What is the percent error of the student’s measurement to the correct number of sig figs?
2%
15. List the following in order of increasing radius: K+, Se2–, Cl–, Na+, S2–
Na+ < K+ < Cl- < S2- < Se2-
16. Which +3 ion has the electron configuration [Ar]3d5?
a. Fe
b. Nb
c. Cr
d. Mo
e. Sc
a. Fe3+
17. Which ion has the smallest radius?
a. Ca2+
b. K+
c. As3-
d. Br -
e. I-
a. Ca2+
18. What is the correct systematic (IUPAC) name for the molecule?
H3C-CH2
H2C-CH-CH2 -CH3
CH2CH2CH3
4-ethyl-heptane
19. What particle is emitted when lead–214, undergoes natural radioactive decay to bismuth–214, Bi?
• beta decay
20. Complete and balance the following transmutation reactions
a.
b.
a. = , b. =
21. Calculate the average atomic mass of lithium, which occurs as two isotopes that have the following atomic masses and abundances in nature: 7.30%, 6.017 amu and 92.7%, 7.018 amu. Consider sig figs when expressing your answer.
6.95 amu
22. Write the electron configuration and orbital diagram for Ag.
[Kr]5s14d10
23.
a. How many -bonds are there in this molecule?
b. How many -bonds are there?
c. Identify the hybridization of carbon atom 1 and oxygen atom 3.
A
B C
1
3
2
a. 11b. 1c. C = sp3, O = sp3
A. B
C
24. A shows examples of __________________ isomers.
25. B and C are examples of ______________ isomers.
geometric
structural
26. A piece of copper (Cp= 0.38J/goC) was heated to 380.3oC and then placed in 150.g of water at 23.5oC. After the copper was sitting in the water for a little while, the water’s temperature was 35.0oC, what was the mass of the copper?
m = 55.0 g
27. When aqueous potassium hydroxide and aqueous copper (II) chloride react, potassium chloride and copper (II) hydroxide are formed. ____. Which of the following represents the correct balanced equation?
a.KH(aq) + CuCl2(aq) KCl(aq) + CuH (s)
b.2KOH(aq) + CuCl2(aq) 2KCl (aq) + Cu(OH)2((s)
c.KOH(aq) + CuCl(aq) KCl (s) + CuOH (s)
d.KOH(aq) + CuCl(aq) KCl (s) + Cu(OH)2(s)
e.b
28. What is the balanced chemical equation for the reaction that takes place between bromine and sodium iodide?
a.Br (l) + NaI (aq) NaBr(aq) + I (s)
b.Br2 (l) + 2NaI (aq) 2NaBr (aq) + I2(s)
c.Br (l) + NaI(aq) NaBrI (s)
d.Br2 (l) + NaI(aq) Br2I2 (aq) + Na (s)
e.This reaction does not take place.
B.
29. Complete and balance the chemical equation for the following single replacement reaction. What are the products of the reaction?
Solid silver reacts with aqueous potassium nitrate