Ice melts when heat energy causes the molecules to move faster, breaking the hydrogen bonds between molecules to form liquid water.
        
             
        
        
        
<h3>
Answer:</h3>
9 mol H₂O
<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>  
- Reading a Periodic Table
- Moles
- Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.
<u>Stoichiometry</u>  
- Using Dimensional Analysis
- Analyzing reactions RxN
<h3>
Explanation:</h3>
<u>Step 1: Define</u>
[RxN - Balanced] 6H₂ + O₂ → 3H₂O
[Given] 18 mol H₂
[Solve] mol H₂O
<u>Step 2: Identify Conversions</u>
[RxN] 6 mol H₂ → 3 mol H₂O
<u>Step 3: Stoich</u>
- [DA] Set up conversion:                                                                                
- [DA] Simplify:                                                                                                  
- [DA] Divide [Cancel out units]:                                                                      
 
        
        
        
Double replacement is happening
        
             
        
        
        
Answer:
2.7724 g
Explanation:
Mass of pre- 1892 pennies = 3.1 g
Abundance = 45.4 %
Mass of post 1892 pennies = 2.5 g
Abundance = 100 - 45.4 = 54.6 %
The average mass is given as = ( 3.1 g   *  45.4 / 100)  +  (2.5g  *  54.6 / 100)
Average Mass = 3.1 * 0.454   +   2.5  *  0.546
Average Mass = 1.4074  + 1.365 = 2.7724 g
 
        
             
        
        
        
<span>Answer: B. Ionic solids have higher melting points than molecular solids.
</span>
This is because the rest are false, as solids are able to melt, and do have melting points. Also, not all solids have the same melting points.