<h3>
Answer:</h3>
1.2 × 10⁻⁸ mol Pb
<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] 7.2 × 10¹⁵ atoms Pb
<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 rules and round. We are given 2 sig figs.</em>
1.19562 × 10⁻⁸ mol Pb ≈ 1.2 × 10⁻⁸ mol Pb
The number of moles present in 29.5 grams of argon is 0.74 mole.
The atomic mass of argon is given as;
Ar = 39.95 g/mole
The number of moles present in 29.5 grams of argon is calculated as follows;
39.95 g ------------------------------- 1 mole
29.5 g ------------------------------ ?

Thus, the number of moles present in 29.5 grams of argon is 0.74 mole.
<em>"Your question seems to be missing the correct symbol for the element" </em>
Argon = Ar
Learn more here:brainly.com/question/4628363
Answer:
The correct answer is no.
Explanation:
Tellurium is a chemical element denoted by Te and having atomic number 52. It is mildly toxic, brittle, silver-white, and rare metalloid. The element is chemically related to sulfur and selenium, all three of which are chalcogens.
Oxygen is a chemical element, that is, a substance, which comprises only one kind of atom. Its official chemical symbol is O and exhibits an atomic number 8, this signifies that an atom of oxygen possesses eight protons in its nucleus. In the given question, it is not likely that tellurium would replace for oxygen, as the two elements are highly unlike.
Answer:
4.214 × 10^23 molecules.
Explanation:
Number of molecules in a substance can be calculated by multiplying the number of moles in that substance by Avagadro's number, which is 6.02 × 10^23.
That is, no. of molecule = n × Avagadro constant
In this case, there are 0.7 moles of fructose. Hence;
number of molecules = 0.7 × 6.02 × 10^23
no. of molecule = 4.214 × 10^23 molecules.