Answer:
The answer to your question is: Initial temperature of copper = 67.1°C
Explanation:
Data
mass Copper = 248 g
volume Water = 390 ml
T1 water = 22.6°C
T2 = 39.9°C
T1 copper = ?
Specific heat water = 1 cal/g°C
Specific heat copper = 0.092 cal/g°C
Formula copper water
Heat is negative for copper because it releases heat
- mCp(T2 - T1) = mCp(T2 - T1)
- (248)(39.9 - T1) = 390 (1)((39.9 - 22.6) Substitution
-9895.2 + 248T1 = 390(17.3) Simplification
-9895.2 + 248T1 = 6747
248 T1 = 6747 + 9895.2
248 T1 = 16642.2
T1 = 16642.2 / 248
T1 = 67.1 °C Result
Answer: D) 1.00 g
Explanation:
According to the Avogadro's law, the volume of gas is directly proportional to the number of moles of gas at same pressure and temperature. That means,
or,
where,
= initial volume of gas = 2.00 L
= final volume of gas = 3.00 L
= initial moles of gas =
= final moles of gas = ?
Now we put all the given values in this formula, we get
Mass of helium =
Thus mass of helium added = (3.00-2.00) g = 1.00 g
Answer:
47.36mL
Explanation:
Using Boyles law equation, which states that:
P1V1 = P2V2
Where;
V1 = initial volume (mL)
V2 = final volume (mL)
P1 = initial pressure (atm)
P2 = final pressure (atm)
Based on the provided information, V1 = 25.3mL, P1 = 152 kPa, V2 = ?, P2 = 0.804atm
First, we need to convert 152kPa to atm by dividing by 101
1kPa = 0.0099atm
152kPa = 1.505atm
P1V1 = P2V2
1.505 × 25.3 = 0.804 × V2
38.08 = 0.804V2
V2 = 38.08/0.804
V2 = 47.36mL
The first step is to find the number of moles of OH⁻ that reacted with the HCl. To do this multiply 2.00L by 1.50M to get 3 moles of Ca(OH)₂. Then you multiply 3 by 2 (there are 2 moles of OH⁻ per every 1 mole of Ca(OH)₂) to get 6 moles of OH⁻. That means that you needed 6 moles of HCl since 1 mole of HCl contains 1 mole of H⁺ and equal amounts H⁺ and OH⁻ reacted with each other. To find the molarity of the HCl solution you need to divide 6mol by 1L to get 6M. Tat means that the concentration of the acid was 6M.
I hope this helps. Let me know if anything was unclear.
