Waves depends on density and elasticity of the medium
<h3>
Answer:</h3>
2 M
<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>Unit 0</u>
- Reading a Periodic Table
- Using Dimensional Analysis
<u>Aqueous Solutions</u>
- Molarity = moles of solute / liters of solution
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
36.7 g CaF₂
300 mL H₂O
<u>Step 2: Identify Conversions</u>
Molar Mass of Ca - 40.08 g/mol
Molar Mass of F - 19.00 g/mol
Molar Mass of CaF₂ - 40.08 + 2(19.00) = 78.08 g/mol
1000 mL = 1 L
<u>Step 3: Convert</u>
<em>Solute</em>
- Set up:
![\displaystyle 36.7 \ g \ CaF_2(\frac{1 \ mol \ CaF_2}{78.08 \ g \ CaF_2})](https://tex.z-dn.net/?f=%5Cdisplaystyle%2036.7%20%5C%20g%20%5C%20CaF_2%28%5Cfrac%7B1%20%5C%20mol%20%5C%20CaF_2%7D%7B78.08%20%5C%20g%20%5C%20CaF_2%7D%29)
- Multiply:
![\displaystyle 0.470031 \ mol \ CaF_2](https://tex.z-dn.net/?f=%5Cdisplaystyle%200.470031%20%5C%20mol%20%5C%20CaF_2)
<em>Solution</em>
- Set up:
![\displaystyle 300 \ mL \ H_2O(\frac{1 \ L \ H_2O}{1000 \ mL \ H_2O})](https://tex.z-dn.net/?f=%5Cdisplaystyle%20300%20%5C%20mL%20%5C%20H_2O%28%5Cfrac%7B1%20%5C%20L%20%5C%20H_2O%7D%7B1000%20%5C%20mL%20%5C%20H_2O%7D%29)
- Multiply:
![\displaystyle 0.3 \ L \ H_2O](https://tex.z-dn.net/?f=%5Cdisplaystyle%200.3%20%5C%20L%20%5C%20H_2O)
<u>Step 4: Find Molarity</u>
- Substitute [M]:
![\displaystyle x \ M = \frac{0.470031 \ mol \ CaF_2}{.3 \ L \ H_2O}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20x%20%5C%20M%20%3D%20%5Cfrac%7B0.470031%20%5C%20mol%20%5C%20CaF_2%7D%7B.3%20%5C%20L%20%5C%20H_2O%7D)
- Divide:
![\displaystyle x = 1.56677 \ M](https://tex.z-dn.net/?f=%5Cdisplaystyle%20x%20%3D%201.56677%20%5C%20M)
<u>Step 5: Check</u>
<em>Follow sig fig rules and round.</em> <em>We are given 1 sig fig as our lowest.</em>
1.56677 M ≈ 2 M
Answer:
= 28.745 g
Explanation:
Half life is the time taken by a radioactive element to decay by half the original amount.
Therefore;
New mass = Original mass × (1/2)^n
Where n is the number of half lives, in this case, n = 20/5.27 = 3.795
Therefore;
New mass = 399 g × (1/2)^3.795
<u> = 28.745 g</u>