4.92 grams / 6 mL = .82 grams / mL
<span>(A) 0.82 g/mL</span>
The product of the complete combustion of any fuel (in this case, acetylene) are indeed water and carbon dioxide.
Balancing the combustion reaction,
C2H2 +(5/2) O2 --> 2CO2 + H2O
The number of moles of C2H2 will be,
(12 g) x (1 mole/26 g) = 6/13 mole
Then, the number of moles of O2 is,
(12 g) x (1 mole/32 g) = 3/8 mole
Therefore the limiting reaction is the O2. Getting the amount of CO2 and H2O produced from balancing,
CO2 = (3/8 moles) x (2 moles CO2/ 5/2 mole O2)(44 g/ 1 mole) = 52.8 g
H2O = (3/8 moles) x (1 mole / 5/2 mole O2)(18 g / 1 mole) = 2.7 g
The time the chocolate bar could power the laptop in hours is 0.00233 hrs.
Since 200 Calories of chocolate bar were burned to power the 100 Watt laptop, we need to find the number of joules on energy in 200 calories of chocolate bar.
Knowing that 4.2 Joules = 1 Calorie, then
200 Calories = 200 × 1 calorie = 200 × 4.2 Joules = 840 Joules
Since the power required by the laptop is 100 W = 100 J/s and Power, P = energy/time
so, time = energy/power
So, the time for the laptop to use 840 J of energy from the chocolate bar at a rate or power of 100 W = 100 J/s is
time = 840 J ÷ 100 J/s = 8.4 s
So, the time in hours is 8.4 s ÷ 3600 s/1 h = 0.00233 hrs (since 1 hr = 3600 s)
So, the time the chocolate bar could power the laptop in hours is 0.00233 hrs.
Learn more about time to power here:
brainly.com/question/17732603
Q1)
As Kemmi pipettes a volume of 25.00 ml of the solution
density of pure propanol is 0.803 g/ml
This means that in 1000 ml of solution - 0.803 g of pure propanol
Therefore in 25.00 ml of solution - 0.803 g x 25.00 ml / 1000 ml
= 0.0201 g
Using molar mass, number of moles can be calculated= 0.0201 g / 60.09 g/mol
= 3.35 x 10⁻⁴ mol
therefore the number of pure propanol moles in exactly 25.00 ml is
3.35 x 10⁻⁴ mol
Q2)
molarity is the concentration of the solution. It can be defined as the number of moles of solute per liter of solution
we know the number of moles in 25.00 ml of solution. When its diluted in a 100.00 ml volumetric flask, number of moles remain constant but now the volume over which the moles of solute are dissolved is increased.
therefore number of moles = 3.35 x 10^(-4) mol
volume over which its dissolved - 100.00 / 10³ dm³
= 1.0000 x10⁻¹ dm³
the molarity = 3.35 x 10⁻⁴ mol / 1.0000 x10⁻¹ dm³
= 3.35 x 10⁻³ mol/dm³
Mass will increase drastically the GPE since mass since mass is a variable in the formula GPE= mgh. 2.
