Answer:
- <em>The two-dimensional set of points that has no beginning or end is described by the undefined geometric term</em> <u>plane.</u>
Explanation:
There are three <em>undefined terms</em><em> in geometry</em>:
They are referred as undefined terms because they are not defined in a formal way, i.e. using mathematically defined words. At the end these terms are abstractions (ideas).
The point has no dimensions, it can be represented by the tip of a sharp pencil.
The line is referred as an infinite set of joined points that extend indefinitely in one direction (from right to left, from north to south), so it has one dimension. The intersection of of two perpendicular walls is an example of what a line is.
Finally, the term to which the question is referred is the plane: an infinite set of joined points that extends in two dimensions. An example of plane is the surface of quite water. The plane does not have depth, only extension; that is why it has only two dimensions.
So, you should remember: points do not have dimensions, lines have one dimension, and planes have two dimensions.
Answer: 19.4 mL Ba(OH)2
Explanation:
H2(g) + Cl2(g) --> 2HCl(aq) (make sure this equation is balanced first)
At STP, 1 mol gas = 22.4 L gas. Use this conversion factor to convert the 100. mL of Cl2 to moles.
0.100 L Cl2 • (1 mol / 22.4 L) = 0.00446 mol Cl2
Use the mole ratio of 2 mol HCl for every 1 mol Cl2 to find moles of HCl produced.
0.00446 mol Cl2 • (2 mol HCl / 1 mol Cl2) = 0.00892 mol HCl
HCl is a strong acid and Ba(OH)2 is a strong base so both will completely ionize to release H+ and OH- respectively. You need 0.00892 mol OH- to neutralize all of the HCl. Note that one mole of Ba(OH)2 contains 2 moles of OH-.
0.00892 mol OH- • (1 mol Ba(OH)2 / 2 mol OH-) • (1 L Ba(OH)2 / 0.230 M Ba(OH)2) = 0.0194 L = 19.4 mL Ba(OH)2
<span>3.68 x 10²⁵ bromine atoms * 1mol/6.02*10²³ atoms=
= 61.13 mol of bromine atoms
1 mol PBr3 ----- 3 mol Br
x mol PBr3 -----61.13 mol Br
x= 1*61.13/3 = 20.4 mol PBr3.
</span>20.4 mol PBr3 <span>contain 3.68 x 10^25 bromine atoms.</span>
Answer:
Sort the lab chemicals in alphabetical order for quick access.
Become familiar with the chemicals to be used, including exposure or spill hazards.
Locate the spill kits and understand how they are used.
Explanation:
There are many chemicals in a laboratory hence they should be sorted out and arranged in alphabetical order so that theory can easily be identified and located whenever they are required.
The properties of each chemical should be known especially hazards connected to exposure or spill of the chemicals.
The students should also familiarize themselves with the contents of spill kits and how they are used.
