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Answer:</h3>
0.002 moles
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Explanation:</h3>
Concept tested: Molarity
We are given;
- Volume of HCl as 20 ml or 0.02 L
- Molarity of HCl solution as 0.10 M
We are required to calculate the number of moles of HCl
What is molarity?
- Molarity is the concentration of a solution in moles per liter
How is it calculated?
- It calculated by dividing number of moles by volume;
- Molarity = Number of moles ÷ Volume
To calculate the number of moles we rearrange the formula;
Moles = Molarity × Volume
In this case;
Moles of HCl = 0.10 M × 0.02 L
= 0.002 moles
Therefore, the number of moles of HCl is 0.002 moles
For this case, we use the equation for an ideal gas which is expressed as PV=nRT where P is the pressure, V is the volume, n is the number of moles and T is the temperature. We calculate as follows:
PV = nRT
T = PV / nR
T = 20 kPa (100 L) / 1 mol (8.314)
T = 240.56 K
Answer:
Explanation:
There are three heat transfers involved.
heat from combustion of propane + heat gained by water + heat gained by calorimeter = 0
q₁ + q₂ + q₃ = 0
m₁ΔH + m₂C₂ΔT + C_calΔT = 0
Data:
m₁ = 2.1 g
m₂ = 280 g
Ti = 25.00 °C
T_f = 26.55 °C
Ccal = 92.3 J·°C⁻¹
Calculations:
Let's calculate the heats separately.
1. q₁
q₁ = 2.1 g × ΔH = 2.1ΔH g
2. q₂
ΔT = T_f - Ti = 26.55 °C - 25.00 °C = 1.55 °C
q₂ = 280 g × 4.184 J·°C⁻¹ × 1.55 °C = 1816 J
3. q₃
q₃ = 92.3 J·°C⁻¹ × 1.55 °C = 143.1 J
4. ΔH
Answer:
a. The apparatus required to purify gypsum sample are: Bunsen burner, beaker, Filter Funnel, stirring rod, the filter paper.
b. Gypsum is a sulfate mineral that is made up of calcium sulfate dihydrate. Step-by-step instruction to purify gypsum sample is as follows:
1. Add water to the gypsum sample in a beaker.
2. Use the stirring rod to mix the mixture well.
3. Filter off the excess solid from the mixture using the filter paper and filter funnel.
4. Put the filtered mixture over the bunsen burner and evaporate the excess water from the mixture.
5. Allow the hot liquid to cool down and filter it again through the filter paper to get the pure gypsum.
please check the attached image, i have given this answer b4
