Answer:
8.61 mL of the HCl solution
Explanation:
The reaction that takes place is:
- 2HCl + Mg(OH)₂ → MgCl₂ + 2H₂O
From the given mass of Mg(OH)₂, we can calculate <u>the moles of HCl that are neutralized</u>:
- 4x10² mg = 400 mg = 0.400g
- 0.400g Mg(OH)₂ ÷ 58.32g/1mol = 6.859*10⁻³ mol Mg(OH)₂
- 6.859*10⁻³ mol Mg(OH)₂ *
3.429x10⁻³ mol HCl
Finally, to calculate the volume of an HCl solution, we need both the moles and the concentration. We can <u>calculate the concentration using the pH value</u>:
= [H⁺]
- 0.0398 M = [H⁺] = [HCl] *Because HCl is a strong acid*
Thus, the volume is:
- 0.0398 M = 3.429x10⁻³mol HCl / Volume
- Volume = 8.616x10⁻³ L = 8.62 mL
There are 4 significant figures
Because of the surface tention.
Answer:
iv. The motion between A & B moves at a further distance than C & D's
v. The cyclist travels 800 meters
vi. It takes approx. 80 seconds
vii. The cyclist's speed is 10 meters per second (m/s)
viii. The cyclist's speed is also 10 meters per second (m/s)
vii. (2) The cyclist's average speed is 10 meters per second (m/s)
Explanation:
Speed is calculated using the formula distance divided by time (d/t)
vii (2) needs further explanation:
Though there is a moment of rest, the cyclist still travels the same speed throughout the entire trip. To check this answer however, you can total the distance and time the cyclist traveled and use speed formula to get 10 meters per second, again.
