Answer:
6.50 grams of the compound X is nitrogen
Explanation:
Step 1: Data given
Mass of compound X = 37.8 grams
Compound contains 17.2 % N
Step 2: Calculate mass of nitrogen
Mass nitrogen = % Nitrogen * total mass
Mass nitrogen = 17.2 % * 37.8 grams = 0.172 * 37.8 grams
Mass nitrogen = 6.50 grams
6.50 grams of the compound X is nitrogen
Answer: 8855 Joules energy is released when 115 g of 
changes from a liquid to a solid at its freezing point.
Explanation:
Latent heat of freezing is the amount of heat released to convert 1 mole of liquid to solid at atmospheric pressure.
Amount of heat released to freeze 1 gram of = 77 J/g
Mass of given = 115 gram
Heat released when 1 g of is freezed = 77 J
Thus Heat released when 115 g of is freezed =
Thus 8855 Joules energy is released when 115 g of changes from a liquid to a solid at its freezing point.
Answer:
pH = 1.6
Explanation:
0 mL NaOH:
⇒ [ H3O+] = M HBr = 0.1 M
⇒pH = -log [H3O+] = 1
30 mL NaOH:
⇒ mol NaOH = 0.1 mol / L * 0.03 L = 3 E-3 mol
⇒ mol HBr = 0.05 L * 0.1 mol/L = 5 E-3 mol
⇒ M HBr = ( 5 E-3 mol - 3 E-3 mol) / 0.08 L = 0.025 M
⇒ pH = - log (0.025) = 1.6
Answer:
Explanation:
Ksp(BaSO4)=1.07×10−10
BaSO₄ → Ba²⁺ + SO₄²⁻
1.07×10⁻¹⁰ = ( Ba²⁺) × ( SO₄²⁻)
but Ba²⁺ = 1.3×10⁻² M
1.07×10⁻¹⁰ = 1.3×10⁻² M × ( SO₄²⁻)
( SO₄²⁻) = 1.07×10⁻¹⁰ / 1.3×10⁻² = 0.823 × 10⁻⁸ M
while Ksp(CaSO4)=7.10×10−5
CaSO₄ → Ca²⁺ + SO₄²⁻
7.10×10⁻⁵ = 2.0×10⁻² × ( SO₄²⁻)
( SO₄²⁻) = 7.10×10⁻⁵ / 2.0×10⁻² = 3.55 × 10⁻³ M
comparing the concentration of sulfate ions, Ba²⁺ cation will precipitate first because the Ba²⁺ requires 0.823 × 10⁻⁸ M sodium sulfate which less compared the about needed by CaSO₄
