We determine the limiting reactant by using the moles present in the equation and the actual moles.
According to equation, ratio of Fe₂O₃ : Al = 1 : 2
Actual moles of Fe₂O₃ = 187.3 / (56 x 2 + 16 x 3)
= 1.17
Actual moles of Al = 94.51 / 27
= 3.5
Fe₂O₃ is limiting. Fe₂O₃ required:
(moles Al)/2 = 3.5/2 = 1.75
Moles to be added = 1.75 - 1.17
= 0.58
Mass to be added = moles x Mr
= 0.58 x (56 x 2 + 16 x 3)
= 92.8 grams
<h2>Steps:</h2>
- Remember that Density = mass/volume, or D = m/v
So firstly, we have to find the volume of the rock. To do this, we need to subtract the volume of water A from the volume of the water B. In this case:
- Water A = 30 mL
- Water B = 40 mL
- 40 mL - 30 mL = 10 mL
<u>The volume of the rock is 10 mL.</u>
Now that we have the volume, we can plug that and the density of the rock into the density equation to solve for the mass.

For this, multiply both sides by 10:

<h2>Answer:</h2>
<u>Rounding to the tenths place, the mass of the rock is 36.8 g, or C.</u>
Answer:
8 mi = 12.875 km
12.875 /60 m
= 0.21458 km / min
11.7 / 0.21458 = 54.52 min
Answer
If the temperature is increased , the number of collision per second increases.
Explanation
Temperature is proportional to the average kinetic energy of a sample of a gas according to the equation PV=n R T. An increased in temperature , increases the kinetic energy of the gas particles which in turn rises the velocity of the gas particles hitting the walls of the container. The more the number of particles the higher the collision rate and greater the pressure as long as the volume of container and the temperature are constant.