Answer:
Solution of isopropanol is 10.25 molal
Explanation:
615 g of isopropanol (C3H7OH) per liter
We gave the information that 615 g of solute (isopropanol) are contained in 1L of water. We need to find out the mass of solvent, so we use density.
Density of water 1g/mL → Density = Mass of water / 1000 mL of water
Notice we converted the L to mL
Mass of water = 1000 g (which is the same to say 1kg)
Molality are the moles of solute in 1kg of solvent, so let's convert the moles of isopropanol → 615 g . 1mol / 60g = 10.25 moles
Molality (mol/kg) = 10.25 moles / 1kg = 10.25 m
Answer is: mass of lithium fluoride is 3,732 grams.
m(solution) = 18,66 g.
ω(solution) = 20% = 20% ÷ 100% = 0,2.
m(LiF) = ?
ω(solution) = m(LiF) ÷ m(solution).
m(LiF) = ω(solution) · m(solution).
m(LiF) = 0,2 · 18,66 g.
m(LiF) = 3,732 g.
Answer:
son 12.6 gramos de HF
Explanation:
Tienes que saber qual es el reactor limitante en este caso es fluoruro con los 20 gramos puedes producer .631 mol qual son 12.6 gramos
Answer:
It take 3.5 *10² min
Explanation:
Step 1: Data given
Mass of the nickel = 29.6 grams
4.7A
Step 2: The balanced equation
Ni2+ (aq- +2e- → Ni(s)
Step 3: Calculate time
W = (ItA)/(n*F)
⇒ W = weight of plated metal in grams = 29.6
⇒ I = current in coulombs per second.
= 4.7
⇒ t = time in seconds.
⇒ A = atomic weight of the metal in grams per mole. = 58.69
⇒ n = valence of dissolved metal in solution in equivalents per mole. = 2
⇒ F = Faraday's constant in coulombs per equivalent. F = 96,485.309 coulombs/equivalent.
29.6 = (4.7 * t * 58.69)/(2*96485309)
t = 20707 seconds
t =345 minutes = 3.5 * 10² min
It take 3.5 *10² min
Answer:
[H⁺] = 1.58 x 10⁻⁷ M.
Explanation:
∵ pOH = - log[OH⁻]
7.20 = - log[OH⁻]
log[OH⁻] = - 7.20
∴ [OH⁻] = 6.31 x 10⁻⁸.
∵ [H⁺][OH⁻] = 10⁻¹⁴.
∴ [H⁺] = 10⁻¹⁴/[OH⁻] = 10⁻¹⁴/(6.31 x 10⁻⁸) = 1.585 x 10⁻⁷ M.