Answer:
D. -1882J
Explanation:
We can solve the energy released in a chemical reaction in an aqueous medium using the equation:
Q = -m*C*ΔT
<em>Where Q is energy (In J),</em>
<em>m is mass of water (45.00g)</em>
<em>C is specific heat of water (4.184J/g°C)</em>
<em>And ΔT is change in temperature (25.00°C - 15.00°C = 10.00°C)</em>
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Replacing:
Q = -45.00*4.184J/g°C*10.00°C
Q = -1882J
Right answer is:
<h3>D. -1882J</h3>
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Answer:
Molality = 7.5 mol/kg
Explanation:
Given data:
Mass of NH₄Cl = 6.30 g
Mass of water = 15.7 g (15.7/1000 =0.016 kg)
Molality = ?
Solution:
Formula of molality:
Molality = Moles of solute / mass of solvent in gram
Now we will first calculate the number of moles of solute( NH₄Cl )
Number of moles = mass/ molar mass
Molar mass of NH₄Cl = 53.491 g/mol
Number of moles = 6.30 g/ 53.491 g/mol
Number of moles = 0.12 mol
Now we will calculate the molality.
Molality = Moles of solute / mass of solvent in gram
Molality = 0.12 mol / 0.016 kg
Molality = 7.5 m
or (m=mol/kg)
Molality = 7.5 mol/kg
Answer:
velocity = 29925×10⁶ m/s
Explanation:
Given data:
Frequency = 35 MHz
Wavelength = 855 m
Velocity = ?
Solution:
MHz to Hz
35×10⁶ Hz
Formula:
<em>velocity = Wavelength × Frequency</em>
velocity = 855 m × 35×10⁶ Hz
velocity = 29925×10⁶ m/s
Hz = s⁻¹
Answer:
the electronic distribution in an atom of x is 14