CHEM 101-Introductory Chemistry I-QUIZ 8/9

1. Carbon tetrachloride has a density of 1.590 g/mL. What is the volume in milliliters of a sample of carbon tetrachloride that has a mass of 1.800 kilograms?

d. 1132 mL

2. If a 50.0 mL sample of gasohol has a mass of 37.5 g, what is the density of the gasohol in grams per cubic centimeter?

b. 0.750 g/cm3

3. The correct formula for tetraphosphorus heptoxide is:

a. P4O6

4. Which of the following is a triatomic molecule of a compound?

c. Ozone (O3)

5. How much heat must be absorbed by 125 g of ethanol to change its temperature from 21.5oC to 34.8oC? The specific heat of ethanol is 2.42 J/(goC).

d. 4.02 kJ

6. The number of neutrons in an element with the electronic configuration 1s22s22p63s23p3 and mass number 31 is

c. 16

7. Strontium 90 (atomic number = 38) is an important and lethal constituent of nuclear fallout. What is the number of protons and electrons in Strontium 90?

b. 38 protons and 38 electrons

8. Which of the following has bonding that is only covalent?

c. CH4

9. The element with electronic structure, 1s22s22p63s23p64s23d104p65s1, is

d. a transition metal

10. Which of the following metals would react with sulfuric acid?

c. iron

11. An emerald has the chemical formula Be3Al2Si16O18. What is the percentage of aluminum in the gemstone?

c. 6.59%

12. When the equation Al(OH)3 + H2SO4 --> Al2(SO4)3 + H2O is balanced the sum of the coefficients of the products is

c. 7

13. Ammonia (NH3) reacts with oxygen to form nitrogen monoxide and water. What is the percent yield of nitrogen monoxide if 8.5 g of ammonia produces an actual yield of 12.0 grams of nitrogen monoxide.

c. 80%

14. The reaction Al(OH)3 + H2SO4 --> Al2(SO4)3 + H2O is an example of a(n)

c. acid-base reaction

15. The molar mass of magnesium chloride is

a. 95.2 grams

16. If a reaction mixture contains 5 moles of substance A and 8 moles of substance B and reacts according to the generic reaction

A + 2B à AB2 ∆Hrxn = 155 kJ

how much heat is emitted or absorbed once the reaction has occurred to the greatest extent possible?

c. 620 kJ emitted

17. How many carbon atoms are there in a 12.5 kg sample of carbon?

c. 6.27 x 1026 atoms

18. When you write the balanced equation for burning the hydrocarbon heptene, C7H14, to completion the sum of the coefficients of the reactants is:

b. 23

19. What is the empirical formula for octene, C8H16?

c. CH2

20. For the reaction

2 Cu2O + C à 4 Cu + CO2

how many moles of carbon dioxide can be formed from 0.450 moles of copper(I) oxide reacting with an excess of carbon?

c. 0.225 moles

21. Write the Lewis structure for the compound strontium chloride.

22. Methyl alcohol (CH3OH) can be synthesized by the reaction of carbon monoxide with hydrogen. How many liters of hydrogen gas, measured at 748 mm Hg and 86oC, are required to synthesize 0.55 moles of methyl alcohol?

T=86C=86+273=359K

V=(1.1*0.0821*359)/(748/760)=32.9 lit

23. Sodium chloride reacts with sulfuric acid to make gaseous hydrogen chloride and solid sodium sulfate. What volume of gas in liters at STP is expected from 5.00 g of sulfuric acid and 10.0 grams of sodium chloride?

v=nrt/P=((2*5/98)(0.08206)(273))/1=2.29L