They go through radioactive decay because when atoms are unstable by going through it they are emitting radiation in natural process and they gain stability by losing energy.
<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
Answer:
135g Na2CO3
Explanation:
I'm going to assume you mean Molality which is mol solute/kg solvent
Molarity would be mol soute/ L solution
we know we have 155g of water which is .155 kg
essentially we have the equation:
mol/kg = 8.20
we substitute .155 in for kg and get:
mol/.155 = 8.20
Solving this gives mol = 1.271
now we must convert to grams using the molar mass
Molar mass Na2CO3 = 106G/mol
so to cancel moles we multiply:
1.271mol x 106g/mol
= 135g
A. A group of related objects that do not send out or receive feedback and cannot modify themselves
Explanation:
An open-loop system is a a group of related objects or systems that cannot send out or receive feedback and modify themselves.
- It is a non-feedback system.
- In this system, the output control system has no effect on whatever input that is fed into the system.
- Output and input in such systems are independent of one another.
- The input and output has no control whatever on each other.
learn more:
Computer programs brainly.com/question/9409412
#learnwithBrainly
check out this article i found it very helpful,
I couldn't find the answer to your question.