Answer:
2H⁺ (aq) + 2OH⁻ (aq) → 2H₂O (l)
General Formulas and Concepts:
- Solubility Rules
- Strong Acids/Bases
Explanation:
<u>Step 1: RxN</u>
HNO₃ (aq) + Ca(OH)₂ (aq) → Ca(NO₃)₂ (aq) + H₂O (l)
<u>Step 2: Balance RxN</u>
2HNO₃ (aq) + Ca(OH)₂ (aq) → Ca(NO₃)₂ (aq) + 2H₂O (l)
<u>Step 3: Ionic Equations</u>
Total Ionic Equation:
2H⁺ (aq) + 2NO₃⁻ (aq) + Ca²⁺ (aq) + 2OH⁻ (aq) → Ca²⁺ (aq) + 2NO₃⁻ (aq) + 2H₂O (l)
<em>Cancel out spectator ions.</em>
Net Ionic Equation:
2H⁺ (aq) + 2OH⁻ (aq) → 2H₂O (l)
Answer:
45.2%
Explanation:
To calculate the percent of an element in a compound we divide the molar mass of the element by the compound and multiply that by 100
First lets find the molar mass of Fluoride
Looking at the periodic table Fluoride has a molecular mass of 18.998 g
Now we need to find the molecular mass of NaF
Looking at a periodic table, Sodium (Na) has a molecular mass of 22.990g and Fluoride has a molecular mass of 18.998 so NaF has a molecular mass of 22.990(1) + 18.998(1) = 41.988g
Now we divide the mass of fluoride by the mass of sodium fluoride and multiply that by 100 to find the percentage of fluoride that is present in NaF
Mass of Fluoride = 18.998g
Mass of Sodium Fluoride = 41.988g
Percentage of fluoride present in NaF = (18.998g / 41.988g) * 100 = 45.2%
Answer:
42 days
Explanation:
Half life = 8.4 days
Starting mass = 40.0 g
Time = ?
Final Mass = 1/16 * 40 = 2.5 g
First Half life;
Remaining mass = 40 / 2 = 20g
Second Half life;
Remaining mass = 20 / 2 = 10g
Third Half life;
Remaining mass = 10 / 2 = 5g
Fourth Half life;
Remaining mass = 5 / 2 = 2.5g
Time = Number of half lives * Duration of half life = 5 * 8.4 = 42 days
Answer: Melting or boiling
Explanation:
Melting or boiling point is another property that scientists can use to identify a substance. Melting point is the temperature at which a substance changes from solid → liquid. Boiling point is the temperature at which a substance changes from liquid → gas.