Answer:
1. 
2. 
Explanation:
Hello,
1. In this case, since the volume of the rock is obtained via the difference between the volume of the cylinder with the water and the rock and the volume of the cylinder with the water only:

Thus, the density turns out:

2. In this case, given the density and mass of aluminum we can compute its volume as follows:

Moreover, as the volume is also defined in terms of width, height and length:

The height is computed to be:

Best regards.
Answer:
0.075 moles of iron oxide would be produced by complete reaction of 0.15 moles of iron.
Explanation:
The balanced reaction is:
4 Fe + 3 O₂ → 2 Fe₂O₃
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
- Fe: 4 moles
- O₂: 3 moles
- Fe₂O₃: 2 moles
You can apply the following rule of three: if by stoichiometry 4 moles of Fe produce 2 moles of Fe₂O₃, 0.15 moles of Fe produce how many moles of Fe₂O₃?

moles of Fe₂O₃= 0.075
<u><em>0.075 moles of iron oxide would be produced by complete reaction of 0.15 moles of iron.</em></u>
Answer: 100kPa
Explanation:
P1 = 3.00 x 10² kPa , P2 =?
T1 = 30°C = 30 +273 = 303k
T2 = —172°C = —172 + 273 = 101k
P1/T1 = P2/T2
3 x 10² / 303 = P2 / 101
P2 = (3 x 10² / 303) x 101
P2 = 100kPa