Salt makes the freezing point of water decrease, so it would freeze at a warmer temperature than regular water
Answer:
- m = 1,000/58.5
- b = - 1,000 / 58.5
1) Variables
- molarity: M
- density of the solution: d
- moles of NaCl: n₁
- mass of NaCl: m₁
- molar mass of NaCl: MM₁
- total volume in liters: Vt
- Volume of water in mililiters: V₂
- mass of water: m₂
2) Density of the solution: mass in grams / volume in mililiters
3) Mass of NaCl: m₁
Number of moles = mass in grams / molar mass
⇒ mass in grams = number of moles × molar mass
m₁ = n₁ × MM₁
4) Number of moles of NaCl: n₁
Molarity = number of moles / Volume of solution in liters
M = n₁ / Vt
⇒ n₁ = M × Vt
5) Substitue in the equation of m₁:
m₁ = M × Vt × MM₁
6) Substitute in the equation of density:
d = [M × Vt × MM₁ + m₂] / (1000Vt)
7) Simplify and solve for M
- d = M × Vt × MM₁ / (1000Vt) + m₂/ (1000Vt)
- d = M × MM₁ / (1000) + m₂/ (1000Vt)
Making the simplistic assumption that the dissolved NaCl(s) does not affect the volume of the solvent water means 1000Vt = V₂
- d = M × MM₁ / (1000) + m₂/ V₂
m₂/ V₂ is the density of water: 1.00 g/mL
- d = M × MM₁ / (1000) + 1.00 g/mL
- M × MM₁ / (1000) = d - 1.00 g/mL
- M = [1,000/MM₁] d - 1,000/ MM₁
8) Substituting MM₁ = 58.5 g/mol
- M = [1,000/58.5] d - [1,000/ 58.5]
Comparing with the equation Molarity = m×density + b, you obtain:
- m = 1,000/58.5
- b = - 1,000/58.5
Answer:
The heat required is 1262.91 joules or 1.26 kilojoules.
Explanation:
The quantity of heat (Q) required to raise the temperature of a substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)
Thus, Q = MCΦ
Since,
Q = ?
Mass of aluminum sample = 33.0g
C = 0.89 J/g℃
Φ = (Final temperature - Initial temperature)
= 68°C - 25°C = 43°C
Then, Q = MCΦ
Q = 33.0g x 0.89 J/g℃ x 43°C
Q = 1262.91 J
Since the heat in joules is 1262.91, obtain heat in kilojoules.
If 1000 joules = 1 kilojoules
1262.91 joules = Z
To get Z, cross multiply
Z x 1000 = 1262.91 x 1
1000Z = 1262.91
Z = 1262.91 / 1000
Z = 1.26291 kilojoules (when placed as 3 significant figures, Z is 1.26 kilojoules)
Thus, the heat required is 1262.91 joules or 1.26 kilojoules.
Hello,
Work is done when a force causes an object to move in the same direction that the force is applied..... Friction reduces efficiency because when two surfaces slide past each other, friction resists their motion, and in real machines, some input work is always used to overcome friction.
Hope this helps!!!! Happy Holidays!!!! (:
Answer:
496 g
Explanation:
Let's consider the reaction between ethanol and oxygen to form acetic acid and water.
CH₃CH₂OH + O₂ → CH₃COOH + H₂O
The molar ratio of CH₃CH₂OH to CH₃COOH is 1:1. The moles of acetic acid produced by the reaction of 8.26 moles of ethanol are:
8.26 mol CH₃CH₂OH × (1 mol CH₃COOH/1 mol CH₃CH₂OH) = 8.26 mol CH₃COOH
The molar mass of acetic acid is 60.05 g/mol. The mass corresponding to 8.26 moles is:
8.26 mol × 60.05 g/mol = 496 g
