Given parameters:
Heat of fusion of water = 334j/g
Mass of ice = 45g
Temperature of ice = 0.0°c
Unknown:
Amount of heat needed to melt = ?
Solution:
This is simply a phase change and a latent heat is required in this process.
To solve this problem; use the mathematical expression below;
H = mL
where m is the mass
L is the heat of fusion of water;
H = 45 x 334 = 15030J
I believe the medulla is the answer.
Iron rusts when in contact with water.
Answer:
1.59 x 10⁻²⁵ J.
Explanation:
- The energy of a photon is calculated Planck - Einstein's equation:
E = h ν
, where
E is the energy of the photon,
h is Planck's constant <em>(h = 6.626 x 10
⁻³⁴ J.s)</em>
ν is the frequency of the photon
-
There is a relation between the frequency (ν
) and wave length (λ).
λ.ν = c,
where c is the speed of light in vacuum (c = 3
.0 x 10
⁸ m/s).
λ = 125 cm = 1.25 m.
<em>Now, E = h.c/λ.</em>
∴ E = h.c/λ = (6.626 x 10
⁻³⁴ J.s) (3
.0 x 10
⁸ m/s) / (1.25 m) = 1.59 x 10⁻²⁵ J.
Answer:
The concentration of the murexide solution is 0.0000745 M
Explanation:
From Beer-Lambert's law,
A = εlc
A = Absorbance = 28.65% = 0.2865
ε = molar absorptivity = 3847 M/cm
l = path length = 1cm
c = concentration in mol/L = ?
c = A/εl = 0.2865/(3847×1) = 0.0000745 mol/L
Hope this Helps!
