Chemistry - June 2006

make ur ***** vibrate?

2006-06-18 08:34:46 · 3 answers · asked by Anonymous

I thought water molecules expanded when they're hot, not when they're cold. It should seem as if there is less water when it freezes than when it's in room temperature, shouldn't it?

2006-06-18 08:09:41 · 11 answers · asked by Anonymous

2006-06-18 08:05:05 · 1 answers · asked by mrkittypong 5

2006-06-18 08:00:34 · 12 answers · asked by clampnugget 2

2006-06-18 06:12:40 · 1 answers · asked by mathiphy 2

2006-06-18 06:11:08 · 3 answers · asked by mathiphy 2

I have to take a drug test for a job and i wanted to kmow if mixing a bit a vineger in a drink really helps clean out ur system or is this just a myth/? NE one have experience or tips on what to do?

2006-06-18 05:58:43 · 13 answers · asked by samantha01_27 2

cotton is subjected to many chemical treatments one of them is antiseptic against fungi and bacteria , would like to know those materials used in this step and if petrochemichals can be used

2006-06-18 05:40:18 · 2 answers · asked by hussameltayeb 2

I am having 35 yrs. exp. in Pigment Mfg. and I can represt related or chemical company in India. Or I can do proccurement job In India fro you. Any company in USA or Europe can offer me such job.

2006-06-18 05:15:44 · 2 answers · asked by vijay k 1

2006-06-18 05:04:37 · 1 answers · asked by Anonymous

i really need this for my chemistry project... i cant find any in the web... the best i found was 22

2006-06-18 04:50:30 · 6 answers · asked by KiloTray 1

i have a 500 gallon tank of water connected to my travel trailer. It looks like it has algae in it.

2006-06-18 04:09:23 · 2 answers · asked by MAMOU 1

2006-06-18 03:48:57 · 5 answers · asked by NEOTEH 4

2006-06-18 03:42:03 · 10 answers · asked by NEOTEH 4

In an arguement about animals or cars supporting people which is better for the environment. I wish to show that while carbon monoxide is a posin it is actually better than the number of animals needed to support our live style.

2006-06-18 03:17:29 · 9 answers · asked by mechunka1 1

1. Which of the following solids consists of atoms or molecules held together only by Van Der Waals forces?
1



a.
carbon dioxide




b.
water




c.
silicon dioxide




d.
copper





2. What is the approximate value of the O-C=O bond angle in ethanoic acid?
1



a.
45 degrees




b.
90 degrees




c.
120 degrees




d.
180 degrees





3. Which of the following does NOT contain hydrogen bonds?
1



a.
Ammonium chloride




b.
Ammonia




c.
Nitric acid




d.
Water





4. In microwave ovens, the wave energy produced is absorbed by certain polar molecules.
Which of the following would absorb microwave energy?
1



a.
Aluminium trichloride




b.
Carbon dioxide




c.
Ethanol




d.
Sodium chloride





5. The grid represents two periods of the Periodic Table, for the elements with proton number from 3 to 18:






P





Q



R


S



An element from 1 group, P, Q, R or S, reacts with an element from another of these groups to produce a compound with a giant covalent structure.
Which are these 2 groups?
1



a.
P and R




b.
Q and R




c.
Q and S




d.
R and S





6. Graphite can be used as a lubricant; diamond cannot. This is because graphite has
1



a.
Mobile ions




b.
A hexagonal arrangement of atoms in the layers




c.
Van Der Waals forces between the layers of atoms




d.
Covalent bonds between atoms in the layers





7. 109.5°

107°

105°

0.096 nm

0.101 nm

0.109 nm

The bond lengths and bond angles in the molecules of methane, ammonia and water may be represented as follows:

What causes this trend in bond angles shown?
1



a.
Increasing repulsion between hydrogen atoms as the bond length decreases




b.
The number of bonding electron pairs in the molecule




c.
A non-bonding electron pair having a lower repulsive force than a bonding electron pair




d.
The number of non-bonding electron pairs in the molecule





8. Which type of bond is responsible for intermolecular forces in liquid tetrachloromethane?
1



a.
Covalent bonding




b.
Hydrogen bonding




c.
Temporary dipole-induced dipole attractions




d.
Permanent dipole-permanent dipole attractions





9. A solution of ammonia in water contains
1



a.
Simple molecules only




b.
Simple molecules and hydrogen bonded molecules only




c.
Simple molecules, hydrogen bonded molecules and ions




d.
Ions only





10. The diagram below shows a liquid flowing from a burette and a charged rod being brought near the flow.

Which liquid would be deflected as shown?
1



a.
Bromine




b.
Hexachloroethane




c.
Cyclohexane




d.
Trichloromethane





11. In which one of the following does ionic bonding occur between the named atoms?
1



a.
Aluminium and chlorine in tetrachloroaluminate ion




b.
Boron and fluorine in boron trifluoride




c.
Hydrogen and chlorine in hydrogen chloride




d.
Hydrogen and sodium in sodium hydride





12. The radius and charge of each of 6 ions are shown in the table below:

Ion
J+
L+
M2+
X-
Y-
Z2-

Radius/nm
0.14
0.18
0.15
0.14
0.18
0.15


The ionic solids JX, LY and MZ are of the same lattice type.

What is the correct order of their lattice energies placing the one with the highest numerical value first?
1



a.
JX > LY > MZ




b.
JX > MZ > LY




c.
LY > MZ >JX




d.
MZ > JX > LY





13. Silicon carbide is a shiny, hard, chemically inert material with a very high melting point. It can be used to sharpen knives and make crucibles. Which type of structure explains these properties?
1



a.
A giant structure with covalent bonds between silicon and carbon atoms




b.
A giant structure containing metallic bonding




c.
A giant layer structure with covalent bonds between atoms and Van Der Waals forces between the layers




d.
A simple molecular structure with covalent bonds between atoms of silicon and carbon











14. A stable molecule containing atoms of the elements X, Y and Z has the following structure:

Which elements could X, Y and Z be?
1



a.
X=N, Y=P, Z=Cl




b.
X=O, Y=S, Z=Cl




c.
X=B, Y=C, Z=H




d.
X=P, Y=Si, Z=H


15. Which one of the following sets of solid elements A, B, C or D includes a giant metallic structure, a macromolecular structure and a simple molecular structure? 1
a. Na Mg Al
b. Mg Al Si
c. C Si Sn
d. Al Si S
16. Which of the following is an example of a substance with a macromolecular structure? 1
a. Aluminium chloride
b. Ice
c. Magnesium oxide
d. Silicon dioxide
17. The molecules listed below are of the general formula XYn, with n more than or equal to 2. In which is the Y-X-Y angle greatest? 1
a. BF3
b. CH4
c. NH3
d. PCl3



18. The sulphite ion may be represented as:

What is the O-S-O bond angle?
1



a.
About 90 degrees




b.
About 107 degrees




c.
About 109.5 degrees




d.
About 117.5 degrees


19. Which of the following statements about the properties associated with ionic and covalent bonds is correct? 1
a. A covalent bond cannot be an electrolyte.
b. The only covalent compounds with high melting points are those in which hydrogen bonds occur.
c. Ionic bonds and covalent bonds cannot both occur in the same compound.
d. Ionic compounds differ from metals in that ionic compounds do not conduct electricity in the solid state



20. Cleavage readily occurs along planes of crystals of ionic solids because the ions in the crystal are 1
a. Arranged in a regular fashion
b. Strongly bonded together
c. Weakly bonded together
d. Charged

2006-06-18 02:52:46 · 5 answers · asked by Professor X 1

what 's diffrent between BMC with ABS?

2006-06-18 00:13:05 · 3 answers · asked by reza m 1

2006-06-18 00:06:48 · 11 answers · asked by thajoba 1

245lb male, answere in cubic litters please

2006-06-18 00:06:19 · 4 answers · asked by Darth yogurt 2

2006-06-17 23:44:38 · 13 answers · asked by chha 1

2006-06-17 23:41:12 · 1 answers · asked by Anonymous

pLs urgent

2006-06-17 23:03:41 · 2 answers · asked by Anonymous

It's better if it's colorless, and oderless.

Obviously shouldent be harmful for human skin.

It's even better if the chemical it self caught fire but will protect the skin from burning for atlest 7 mins

2006-06-17 21:00:32 · 10 answers · asked by Anonymous

2006-06-17 20:57:46 · 4 answers · asked by BHAVANA 1

can you please give me the meaning of significant figure and give me the example

2006-06-17 19:53:51 · 3 answers · asked by aira_love21@yahoo.com 1

thanks for your concern.

2006-06-17 19:49:20 · 2 answers · asked by paulaine 1

just the 5 important branches of chemistry

2006-06-17 19:39:59 · 11 answers · asked by aira_love21@yahoo.com 1

2006-06-17 19:20:03 · 5 answers · asked by mathiphy 2

give me the 3 steps in proposing a scientific law

2006-06-17 18:58:38 · 2 answers · asked by aira_love21@yahoo.com 1

2006-06-17 17:39:03 · 11 answers · asked by Anonymous