Biology Forums - Study Force

1.  Which element has the largest atomic radii?
a. I    b. F    c. Cl        d. Br

2.  Draw Lewis structure of PCl3. How many non-bonding electrons are on the central P atom in PCl3 ?
A. 1 B. 2 C. 3 D. 4

3.   A major principle of chemistry is that the observed (macroscopic) properties of a substance are related to its _____ structure.
A. crystalline B. isothermal C. microscopic D. intensive

4.  What is the molecular formula for an alkane with 13 carbon atoms in its molecular structure.
A. CH13 B. C13H28 C. C26H13 D. C28H14

5.  What is the condensed formula for 3-hexene?
A. CH3-CH-CH-CH-CH-CH3
B. CH3CH2CH2CH2CH2CH3
C. CH3CHCH2CH2CH2CH3
D. CH3CH2CHCHCH2CH3

6.  How much energy (calories) is needed to raise 12.0 grams ethanol at 24.0 oC to 42.0 oC? specific heat of ethanol = 0.58 cal/g oC
A. 18.5 cal B. 99.0 cal C. 125.2 cal D. 341.4 cal

7.  A sample of sulfur dioxide occupies a volume of 652 mL at 40.0 oC and 720 mm Hg. What volume will the sulfur dioxide occupy at 0 oC, and 1 atm of pressure?
A. 140 mL B. 0.540 L C. 825 mL D. 0.375 L

8.  At what pressure would 0.150 mole of nitrogen gas at 23.0 °C occupy 8.90 L?
A. 0.200 atm B. 1250 mm Hg C. 0.724 atm D. 311 mm Hg

9.  Which of the following is an alkyne?
A. CH3CH2CH2CH3
B. CH3CHCH2
C. CH3CH2CH2CCCH2CH3
D. CH2CHCH2CHCHCH2CH3

10.  Pentane C5H12 reacts with oxygen gas to produce carbon dioxide and water. How many grams of carbon dioxide will be produced by the reaction of 108.0 grams of pentane? Oxygen is in excess.
C5H12 + 8O2 → 5CO2 + 6H2O
A. 333.0 g B. 216.0 g C. 220.0 g D. 54.0 g

11.  Aluminum hydroxide reacts with sulfuric acid to produce aluminum sulfate and water. How many grams of aluminum hydroxide are necessary to produce 108 grams of water?
2Al(OH)3 + 3H2SO4 → Al2(SO4)3 + 6H2O
A. 26.0 g B. 54.0 g C. 156.0 g D. 0.365 g

This should help :down:

(https://biology-forums.com/gallery/47/6_16_08_16_11_17_54.jpeg) (https://biology-forums.com/index.php?action=gallery;sa=view&id=23714)


(https://biology-forums.com/gallery/47/6_16_08_16_11_18_52.png) (https://biology-forums.com/index.php?action=gallery;sa=view&id=23715)
/me 2 questions per thread, please :sweat:

Hi,

It's C


equation: C5H12 + O2 --> CO2  + H2O
balanced:  C5H12 + 8O2 --> 5CO2  + 6H2O
108g C5H12* (1mole C5H12/72.15g C5H12) * (5 moles CO2/1 mole C5H12) * (44g CO2/ 1 mole CO2) = 329.31~329.3 g of CO2

equation: Al(OH)3  + H2SO4  --> Al2(SO4)3 + H2O
balanced: 2Al(OH)3  + 3H2SO4  --> Al2(SO4)3 + 6H2O

108g H2O * (1 mole H2O / 18g H2O)  * (2 moles Al(OH)3 / 6 moles H2O) * (78 g Al(OH)3  / 1 mole Al(OH)3) = 156 g Al(OH)3

Hope this helps