Average atomic mass is the weighted average atomic masses with regard to the relative abundance of the isotopes
average atomic mass of Li = relative abundance of Li-6 x mass of Li-6 + relative abundance of Li-7 x mass of Li-7
average atomic mass of Li = (7.42% x 6.0151 a.m.u) + (92.58% x 7.0160 a.m.u)
= 0.446 + 6.495
= 6.941 amu
average atomic mass of Li is 6.941 amu
Answer:
[Cl-18]⁻ & [Cl-20]⁻
Explanation:
By definition isotopes are elements with the same number of protons by different number of neutrons. Elements X-18 & X-20 have 17 protons and represent Chlorine isotopes Cl-18 & Cl-20 each with 17 protons and 18 electrons to give the isotopes a -1 oxidation state. Both isotope of chlorine have 7 electron in its valence shell and 10 electrons in its core structure. Gaining 1 electron fills the valence octet and establishes a -1 oxidation state.
Not 100% sure but I believe it is C.
Hello!
The Chemical reaction is the following:
2F₂(g) + 2 H₂O(g) → O₂(g) + 4HF(g)
If we assume that all the gases are ideal gases,
we can describe the coefficients of this reaction as Volume rather than moles, so we can apply the following equations:

So,
2 L of Water Vapor reacts with the fluorine; and
1 L of Oxygen and
4 L of Hydrogen Fluoride are produced.
Have a nice day!
<u>Given:</u>
Mass = 68 kg
Power = 65 W
<u>To determine:</u>
Calories burned during an 8.0 hr sleep
<u>Explanation:</u>
Energy is expressed as:
Energy = Power * Time
Now, the unit of power = Watt (W)
1 W = 1 J/s i.e. 65 W = 65 J/s
Time = 8 hrs = 8 * 3600 s = 28800 s
Energy = 65 J/s * 28800 s = 1872000 J
Convert Joules (J) to calories (cal)
1 cal = 4.184 J
The calculated energy = 187200 J * 1 cal/4.184 = 447418 cal
Ans: The man burns nearly 447.4 kcal during an 8 hr sleep