Answer:
a. Amadeo Avogadro (1776-1856) was the author of Avogadro's Hypothesis in 1811, which, together with Gay-Lussac's Law of Combining Volumes, was used by Stanislao Cannizzaro to elegantly remove all doubt about the establishment of the atomic weight scale at the Karlsruhe Conference of 1860. The name "Avogadro's Number" is just an honorary name attached to the calculated value of the number of atoms, molecules, etc. in a gram mole of any chemical substance. Of course if we used some other mass unit for the mole such as "pound mole", the "number" would be different than 6.022 x 1023.
b. The first person to have calculated the number of molecules in any mass of substance was Josef Loschmidt, (1821-1895), an Austrian high school teacher, who in 1865, using the new Kinetic Molecular Theory (KMT) calculated the number of molecules in one cubic centimeter of gaseous substance under ordinary conditions of temperature of pressure, to be somewhere around 2.6 x 1019 molecules. This is usually known as "Loschmidt's Constant.
Task 2
a.
Percent composition is the percent by mass of each element present in a compound. Water, H2O, is the first example. One mole of water is 18.0152 grams. In that compound, there are two moles of H atoms and 2 x 1.008 = 2.016 grams. That's how many grams of hydrogen are present in one mole of water. this is an example. i don't know what you are describing though. i need more info for this question
b. 6.022 to 6.023 x 10^23
c. i don't know what this one is since there is nothing to describe the unknown liquid.
d. Yes a killer, but not a specific person
Explanation:
Answer:
to watered our source of food
the "PLANTS & TREES"
<span>The correct answer is, Alkali Metals</span>
<h3>
Answer:</h3>
CdS
<h3>
Explanation:</h3>
<u>We are given;</u>
- % of cadmium is 78%
- % of sulfur is 22.0%
We are required to determine the empirical formula of cadmium sulfide
<h3>Step 1 : Determine the number of moles of Cadmium and sulfur </h3>
Assuming the mass of the cadmium sulfide is 100 g
Mass of cadmium is 78 g
Mass of sulfur is 22 g
But;
Moles = Mass ÷ Molar mass
Molar mass of Cadmium = 112.411 g/mol
Moles of Cadmium = 78 g ÷ 112.411 g/mol
= 0.694 moles
= 0.69 moles
Molar mass of sulfur is 32.065 g/mol
Moles of sulfur = 22 g ÷ 32.065 g/mol
= 0.686 moles
= 0.69 moles
<h3>Step 3: Determine the whole number mole ratio of Cadmium to sulfur</h3>
Cadmium : Sulfur
Cd : S
0.69 moles : 0.69 moles
0.69/0.69 : 0.69/0.69
1 : 1
Therefore, the empirical formula of greenockite is CdS
Ca(NO3)2
Ca = 1 atom
O = 6 atoms
N = 2 atoms
Answer C
