Answer:
0.74 moles of oxygen are required for combustion
Explanation:
Given data:
Number of moles of oxygen required = ?
Mass of Mg = 35.5 g
Solution:
Chemical equation:
2Mg + O₂ → 2MgO
Number of moles of Mg:
Number of moles = mass/molar mass
Number of moles = 35.5 g/ 24 g/mol
Number of moles = 1.48 mol
Now we will compare the moles of Mg with oxygen.
Mg : O₂
2 : 1
1.48 : 1/2×1.48 = 0.74 mol
0.74 moles of oxygen are required for combustion.
Answer:
2s
Explanation:
Given parameters:
Acceleration of the truck = 15m/s²
change in Velocity = 30m/s
Unknown:
Time taken for the body to slow down = ?
Solution:
Acceleration is the rate of change of velocity ;
Acceleration =
time =
Now insert the parameters and solve;
time = = 2s
Answer: The density of glycerine is
Explanation: We are given density of glycerine in which is
To convert t into , we are given conversion rates:
454 grams = 1 pound
So, 1 gram will be equal to
Similarly,
So, will be equal to
Converting the density of glycerin from to using above conversion rates, we get:
Density of glycerin is
Answer:
-368.62 kJ/mol
Explanation:
[(2 x - 470.11 kJ/mol) ( 0kJ/mol)] - [ 2 x -285.8 kJ/mol) (2x 0 kj/mol)] = -368.62 kJ/mol
Answer:
The correct answer is 0.020 atm.
Explanation:
Partial pressure is calculated by using the formula,
Partial pressure = Mole fraction × Total pressure
The partial pressure of oxygen in a mixture can be calculated by using the formula,
Mole fraction of oxygen in mixture = Number of moles of oxygen / No. of moles of oxygen + No. of moles of Helium
(1 gg or gigagram is equal to 10⁹ grams)
= 2 × 10⁹/32 /2 × 10⁹/32 + 98 × 10⁹ / 4
= 2.54 × 10⁻³
Now the partial pressure of oxygen = Mole fraction of oxygen × Total pressure of oxygen
= 2.54 × 10⁻³ × 8.0 atm
= 0.02032 atm
= 0.020 atm