Chemistry

Replies / Views	Last post
From its atomic number of 15, it is possible to predict that the phosphorus atom Started by Hawke	1 Replies 1,512 Views	May 28, 2013 by Melanie
Electrons exist only at fixed levels of potential energy. However, if an atom ab Started by Hawke	1 Replies 2,429 Views	May 28, 2013 by Melanie
The atomic number of nitrogen is 7. Nitrogen-15 is heavier than nitrogen-14 beca Started by Hawke	1 Replies 1,968 Views	May 28, 2013 by Melanie
An atom has 6 electrons in its outer shell. How many unpaired electrons does it Started by Hawke	1 Replies 1,976 Views	May 28, 2013 by Melanie
One difference between carbon-12 ( ) is that carbon-14 ( ) has A) two more proto Started by Hawke	1 Replies 1,046 Views	May 28, 2013 by Melanie
In what way are elements in the same column of the periodic table the same? A) T Started by Hawke	1 Replies 880 Views	May 28, 2013 by Melanie
What factors are most important in determining which elements are most common in Started by Hawke	1 Replies 767 Views	May 28, 2013 by Melanie
Which of the following statements is false? A) Carbon, hydrogen, oxygen, and nit Started by Hawke	1 Replies 762 Views	May 28, 2013 by Melanie
Trace elements are those required by an organism in only minute quantities. Whic Started by Hawke	1 Replies 1,347 Views	May 28, 2013 by Melanie
How many electrons does an atom of sulfur have in its valence shell (see the fig Started by Hawke	3 Replies 1,236 Views	May 28, 2013 by coco
In the figure above, how many unpaired electrons does phosphorus have in its val Started by Hawke	3 Replies 1,035 Views	May 28, 2013 by coco
Measurements show that the pH of a particular lake is 4.0. What is the hydrogen Started by Hawke	2 Replies 1,023 Views	May 30, 2013 by Hawke
Measurements show that the pH of a particular lake is 4.0. What is the hydroxide Started by Hawke	2 Replies 891 Views	May 30, 2013 by Hawke
A slice of pizza has 500 kcal. If we could burn the pizza and use all the heat t Started by Hawke	2 Replies 1,232 Views	May 30, 2013 by Hawke
How many grams of acetic acid (C2H4O2) would you use to make 10 L of a 0.1 M aqu Started by Hawke	2 Replies 847 Views	May 30, 2013 by Hawke
Assume that acid rain has lowered the pH of a particular lake to pH 4.0. What is Started by Hawke	1 Replies 982 Views	May 30, 2013 by Celeste
One of the buffers that contribute to pH stability in human blood is carbonic ac Started by Hawke	1 Replies 1,189 Views	May 30, 2013 by Celeste
Which of the following statements is true about buffer solutions? A) They mainta Started by Hawke	1 Replies 821 Views	May 31, 2013 by coco
The element present in all organic molecules is A) hydrogen. B) oxygen. C) carbo Started by federox	1 Replies 682 Views	Jun 2, 2013 by coco
The complexity and variety of organic molecules is due to A) the chemical versat Started by federox	2 Replies 800 Views	Jun 2, 2013 by federox
The experimental approach taken in current biological investigations presumes th Started by federox	2 Replies 951 Views	Jun 2, 2013 by federox
Differences among organisms are caused by A) large differences in elemental comp Started by federox	2 Replies 1,295 Views	Jun 2, 2013 by federox
Which of the following people was the first to synthesize an organic compound, u Started by federox	2 Replies 792 Views	Jun 2, 2013 by federox
Stanley Miller's 1953 experiments proved that A) life arose on Earth from simple Started by federox	2 Replies 1,126 Views	Jun 2, 2013 by federox
Hermann Kolbe's synthesis of an organic compound, acetic acid, from inorganic su Started by federox	2 Replies 1,520 Views	Jun 2, 2013 by federox