Answer:
115060 J
Explanation:
From the question given above, the following data were obtained:
Mass (M) = 500 g
Initial temperature (T1) = 20 °C
Final temperature (T2) = 75 °C
Change in temperature (ΔT) = 55 °C
Specific heat capacity (C) = 4.184 J/g°C
Heat (Q) required =?
The heat required to change the temperature of the water can obtained as follow:
Q = MCΔT
Q = 500 × 4.184 × 55
Q = 115060 J
Therefore, the heat needed to change the temperature of the water is 115060 J.
Answer:
Batteries store chemical energy
Explanation:
It would be C
2 kg x 1000 g/kg x 1mol/18.02 x 6.03 kj/mol = 669kj
25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)
<h3>Explanation</h3>
The process:
.
How many moles of this process?
Relative atomic mass from a modern periodic table:
- K: 39.098;
- N: 14.007;
- O: 15.999.
Molar mass of 
:
.
Number of moles of the process = Number of moles of dissolved:
.
What's the enthalpy change of this process?
for 
. By convention, the enthalpy change 
measures the energy change for each mole of a process.
.
The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.
Answer:
1L
Explanation:
First, let us calculate the number of mole present in 20g of NaOH. This is illustrated below:
Mass = 20g
Molar Mass of NaOH = 23 + 16 + 1 = 40g/mol
Number of mole =?
Number of mole = Mass /Molar Mass
Number of mole of NaOH = 20/40 = 0.5mol
From the question given, we obtained the following data:
Molarity = 0.5M
Mole = 0.5mole
Volume =?
Molarity = mole /Volume
Volume = mole /Molarity
Volume = 0.5/0.5
Volume = 1L
