Explanation:
total heat = Heat required to convert 2 kg of ice to 2 kg of water at 0 °C + Heat required to convert 2 kg of water at 0 °C to 2 kg of water at 20 °C.
Heat=mhfg+mCpΔT
Here, m ( mass of ice) = 2 kg
hfg (latent heat of fusion of ice) = 334 KJ
Cp of water (specific heat) = 4.187 KJ/Kg-K
ΔT(Temperature difference) = 20 °C
Therefore, Heat required = 2 x 334 + 2 x 4.187 x (20 - 0 )
Heat reqd= 835.48 KJ
Therefore, to melt 2 kg of ice 835.48 KJ of heat is required.
Answer:
2.67 mL
Explanation:
The following data were obtained from the question:
Mass of tetracycline = 2 mg
Density of tetracycline = 0.75 mg/mL
Volume of tetracycline =?
We can obtain the volume of the tetracycline that should be given to the patient by applying the following equation:
Density = mass /volume
0.75 = 2 / volume
Cross multiply
0.75 × Volume = 2
Divide both side by 0.75
Volume = 2/0.75
Volume = 2.67 mL
Therefore, the volume of the tetracycline that should be given to the patient is 2.67 mL
Answer:
4.59 × 10⁻³⁶ kJ/photon
Explanation:
Step 1: Given and required data
- Wavelength of the violet light (λ): 433 nm
- Planck's constant (h): 6.63 × 10⁻³⁴ J.s
- Speed of light (c): 3.00 × 10⁸ m/s
Step 2: Convert "λ" to meters
We will use the conversion factor 1 m = 10⁹ nm.
433 nm × 1 m/10⁹ nm = 4.33 × 10⁷ m
Step 3: Calculate the energy (E) of the photon
We will use the Planck-Einstein's relation.
E = h × c/λ
E = 6.63 × 10⁻³⁴ J.s × (3.00 × 10⁸ m/s)/4.33 × 10⁷ m
E = 4.59 × 10⁻³³ J = 4.59 × 10⁻³⁶ kJ
