<span>128 g/mol
Applying Graham's law of effusion, we can utilize the formula:
r1/r2 = sqrt(m2/m1)
where
r1 = effusion rate of gas 1
r2 = effusion rate of gas 2
m1 = molar mass of gas 1
m2 = molar mass of gas 2
Given that the atomic weight of oxygen is 15.999, the molar mass of O2 = 2 * 15.999 = 31.998.
We can now insert the known values into Graham's equation to find m2.
r1/r2 = sqrt(m2/m1)
2/1 = sqrt(m2/31.998)
4/1 = m2/31.998
Thus, we find m2 to be 127.992.
Rounding to three significant figures yields 128 g/mol</span>
Answer:
Explanation:
a) Iron has the tendency to undergo rusting -- this is a chemical property as it involves a reaction with water and air.
b) Precipitation in industrialized areas often has an acidic nature -- this is also a chemical property due to its interaction with bases or metals.
c) Hemoglobin is red in color -- this is a physical property since it doesn't entail any chemical reactions.
d) When water is left out in sunlight, it evaporates gradually -- this is a physical property because the process can easily be reversed, classifying it as a physical change.
e) During photosynthesis, plants convert carbon dioxide into more complex molecules -- this demonstrates a chemical property since it involves chemical reactions.
What precisely is being followed here?
1. Stars originate within clouds of gas and dust referred to as nebulas. 2. These clouds are drawn together by gravitational forces. 3. Once sufficient heat and pressure accumulate, nuclear fusion commences, representing the birth of a star.
Answer:
Mendeleev categorized thallium (Tl) alongside lithium (Li), sodium (Na), potassium (K), rubidium (Rb), and cesium (Cs)
Explanation:
Characteristics of Thallium:
Thallium is a dense metal represented by the symbol Tl. It belongs to the 13th group and 6th period of the modern periodic table. The element is quite malleable and has a +3 oxidation state. It is rarely found in its elemental form in nature.
Mendeleev associated thallium with lithium and sodium because he observed that these elements, including Li and Na, form compounds with a single atom of chlorine (Cl), similar to the formation of TlCl by thallium (Tl). Thus, he classified Tl along with these similar elements.
Distinction of Thallium from the other five elements:
Unlike Li, Na, K, Rb, and Cs that exhibit a +1 oxidation state, Tl has a +3 oxidation state.
