2130 cal is how much is released qhen 30 g of water at
Answer:
8.8 × 10⁻³ g/L
Explanation:
NaF is a strong electrolyte that ionizes according to the following reaction.
NaF(aq) → Na⁺(aq) + F⁻(aq)
Then, the concentration of F⁻ will also be 0.10 M.
In order to find the solubility of PbF₂ (S), we will use an ICE Chart.
PbF₂(s) ⇄ Pb²⁺(aq) + 2 F⁻(aq)
I 0 0.10
C +S +2S
E S 0.10 + 2S
The solubility product (Kps) is:
Kps = 3.6 × 10⁻⁸ = [Pb²⁺].[F⁻]² = S . (0.10 + 2S)²
In the term 0.10 + 2S, 2S is negligible in comparison with 0.10 and we can omit it to simplify calculations.
Kps = 3.6 × 10⁻⁸ = S . (0.10)²
S = 3.6 × 10⁻⁵ M
The molar mass of PbF₂ is 245.20 g/mol. The solubility of PbF₂ in g/L is:
3.6 × 10⁻⁵ mol/L × 245.20 g/mol = 8.8 × 10⁻³ g/L
B because willingness shows confidence in your answer
Answer:
Explanation:
When an object goes on a circular movement, it has a centripetal acceleration that always points toward the center of the circle, it is the responsible of the change of direction in the movement of the object. and that centripetal acceleration is related with the speed in the next way:
, with v the speed, r the radius of the track that is half of the diameter (22.5 m)
Answer:
The work done on the object by the force accelerating it is 520.31 J
Explanation:
Given;
mass of an object = 4.3 kg
horizontal velocity of the object, v = 11 m/s
time of acceleration, t = 3.4 s
work done is given as the product of force and distance
Work done = Fd
horizontal distance traveled by the object within 3.4 s, is calculated as follows;
X = Vt + ¹/₂gt², gravity has little or no influence on horizontal displacement, thus g = 0
X = Vt
X = 11*3.4 = 37.4 m
Force on the object, F = ma = m(v/t) = 4.3(11/3.4) = 13.912 N
work done = Fd = 13.912 x 37.4 = 520.31 J
Therefore, the work done on the object by the force accelerating it is 520.31 J
