Nitrogen, for example, is a gas that liquefies at about −200° C and freezes around −210° C, whereas bismuth is a solid melting at 271° C and boiling at about 1,560° C.
I use small cardboard<span> boxes for organizing drawers, etc,---also break them down and use it in the garden to kill weeds, and I add some to my compost. ... side to one edge that's somewhat shorter </span>than<span> the magazine, to enable one to remove one magazine without removing the </span>whole<span> box from the shelf.</span>
The answer is volume is directly proportional to the number of moles. I hope this helps!!
21. change in temperature, change in color, or noticeable odor (after reaction has begun)
22. Picture... Wasn't so sure about this since no charge was given, so I suspected it has a charge of 2. If you have more information on this I would be glad to help, and I can't tell what is happening with the calculations given. It would be helpful if you can add spaces or put a line break.
23. An ion is an atom or molecule with an electric charge. It is formed when atoms lose or gain electrons. There are two types of ions: cations (net positive charge) and anion (net negative charge).
24. Picture
25. a) dinitrogen tetrahydride
b) phosphorus triiodide
c) lithium hydroxide
Answer:
A) False
B) True
Explanation:
The question is incomplete. The complete question is as follows.
There are two statements. Identify which statement is true or false.
A) For any substance, solid, liquid or gas, mass increases as volume increases.
B) Density represents mass per volume.
Statement A
- Mass is defined as the amount of matter in an object. Its fixed and can't be changed.
- Volume on the other hand is the amount of space an object takes up.
Since the amount of matter is fixed, an increase in volume doesn't cause an increase in mass. For example, a test tube, with a volume of 10ml, contains liquid fragrance. When heated, the fragrance vaporizes and fill the entire room, until you can smell it in every corner. Note that previously the fragrance of same mass was occupying a 10ml space in the test-tube. After heating, the same mass of fragrance occupied the entire room (volume increased but mass remained constant).
It happened because as the fragrance is heated, the space between molecules increases causing them to occupy more space BUT in the whole scenarios, the number of molecules stayed unaffected. <u>Hence statement A is false.
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Statement B
Density measures the compactness of the substance. It's defined as the amount of mass per unit volume. It increases as the atoms/molecules in a substance comes closer. Density of solids are greatest as the atoms/molecules are tightly packed together. It is least in gases as the molecules are far apart from each other. <u>Hence the statement is true.
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