<h3>
Answer:</h3>
251 mol Xe
<h3>
General Formulas and Concepts:</h3>
<u>Math</u>
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
<u>Chemistry</u>
<u>Atomic Structure</u>
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<u>Stoichiometry</u>
- Using Dimensional Analysis
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[Given] 1.51 × 10²⁶ atoms Xe
[Solve] moles Xe
<u>Step 2: Identify Conversions</u>
Avogadro's Number
<u>Step 3: Convert</u>
- [DA] Set up:
- [DA] Multiply/Divide [Cancel out units]:
<u>Step 4: Check</u>
<em>Follow sig fig rule and round. We are given 3 sig figs.</em>
250.747 mol Xe ≈ 251 mol Xe
Answer:
B) exothermic.
Explanation:
Hello!
In this case, we need to keep in mind that exothermic reactions release heat, so they increase the temperature as the final energy is less than the initial energy; in contrast, endothermic reactions absorb heat, so they decrease the temperature as the final energy is greater than the initial energy.
In such a way, when a dissolution process shows off a negative enthalpy of dissolution, we infer it is an exothermic process due to the aforementioned; therefore, the answer is:
B) exothermic
.
Best regards!
Answer:
The ocean currents are too strong by the Amazon River to form deltas.
Explanation:
The Atlantic has sufficient wave and tidal energy to carry most of the Amazon's sediments out to sea, thus the Amazon does not form a true delta. The great deltas of the world are all in relatively protected bodies of water, while the Amazon empties directly into the turbulent Atlantic.
The activity series goes top to bottom, most active to least active elements, going: Li, K, Ba, Sr, Ca, Na, Mg, Mn, Zn, Fe, Cd, Co, Ni, Sn, Pb, H, Cu, Ag, Hg, Au.
Thus, your list of metals would go from most reactive to least reactive: Li, K, Mg, Zn, Fe, Cu, Au
It is energetically favorable for all atoms to have a complete outer
electron shell. Loosely, the atoms on the left hand side of the periodic
table only have a few extra electrons in their outer shell so it is
energetically favorable for them to lose them. The atoms on the right
hand side of the periodic table almost have enough electrons in their
outer shell and so they have a tendency to gain them.
Once electrons have left an electron shell, an atom will have a positive
charge because it has more protons (positive charges) than electrons
(negative charges). Similarly, an electron which has gained electrons to
complete its outer shell will have a negative charge because it now has
more electrons (negative charge) than protons (positive charge).
