Answer:
Final temperature of water is 83.8°C
Explanation:
In 500.0mL of a 6.00M NaOH solution, there are:
0.5000L × (6.00mol NaOH/ L) = <em>3.00moles of NaOH</em>
As the heat involved in dissolution is 44.5 kJ/mol, when the solution is dissolved:
44.5kJ/mol × 3.00moles = 133.5kJ = 133500J
Using coffee-cup calorimeter equation:
q = m×C×ΔT
<em>Where q is heat, m is mass of water (500.0g), C is specific heat of water (4.186J/g°C) and ΔT is change in temperature</em>
<em />
133500J = 500.0g×4.186J/g°C×(X-20.0°C)
63.8 = (X-20.0°C)
83.8°C = X
<em>Final temperature of water is 83.8°C</em>
Answer:
You first need to construct a balanced chemical equation to describe the reaction:
KOH + HNO3 ---------> KNO3 + H2O
Work out the no. moles of HNO3 being neutralized:
Moles = Volume x Concentration = (25/1000) x 0.0150 = 0.000375 moles
From the balanced equation the molar ratio of KOH to HNO3 is 1:1 so you also need 0.000375 moles of KOH to neutralise the nitric acid
Now you can work out the volume of KOH required:
Volume = Moles/Concentration = (0.000375)/0.05 = 0.0075 dm^3 = 7.5 cm^3
They start with the numbers u need to know in order to slove the problem and there has to be a story behind it
Answer:
V₂ = 45.53 L
Explanation:
Given data:
Initial temperature = 850 K
Initial volume = 65 L
Initial pressure = 450 KPa
Final temperature = 430 K
Final pressure = 325 KPa
Final volume = ?
Solution:
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 450 KPa× 65 L × 430 K / 850 K × 325KPa
V₂ = 12577500 KPa .L. K / 276250 K. KPa
V₂ = 45.53 L